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Common DOS Commands Essential Tools under DOS Common Error Messages at the DOS Command Line
Multimedia under DOS Ways to network under DOS Use and setup of hardware devices under DOS
DOS system maintenance Memory configuration under DOS Commands and configuration of the CONFIG.SYS file
DOS batch files Undocumented DOS commands and parameters
Common DOS Commands
If you want to operate and use DOS, knowing some common commands is very important. Below are the uses of some commands.
A filename is made up of the file path and the filename together, such as C:\DOS\COMMAND.COM.
DIR displays files and folders (directories).
Usage: DIR
It has many options, such as /A meaning display all files (including those with hidden and system attributes), /S meaning also display files in subfolders, /P meaning paged display, /B meaning display filenames only, and so on.
For example, DIR A*.EXE /A /P
This command displays, page by page, all files (folders) in the current folder whose names start with A and whose extension is EXE.
CD or CHDIR changes the current folder.
Usage: CD
If no folder name is given, it displays the current path.
MD or MKDIR creates a folder.
Usage: MD folder name
RD or RMDIR deletes a folder.
Usage: RD folder name
Note: this folder must be empty.
DEL or ERASE deletes files.
Usage: DEL/ERASE filename
COPY copies files.
Usage: COPY filename1
For example, COPY /B A+B C
This command combines the two binary files A and B into one file C.
TYPE displays file contents.
Usage: TYPE filename
REN or RENAME changes a filename; in DOS7 it can also change a folder name.
Usage: REN file(folder)name1 file(folder)name2
EDIT edits files; in DOS7 it can also edit binary files.
Usage: EDIT
For example, EDIT /70 C:\COMMAND.COM
This command edits the file C:\COMMAND.COM in binary mode.
FORMAT formats a disk.
Usage: FORMAT drive
It has many options, such as /Q for quick format, /U for unconditional format (that is, recovery with commands like UNFORMAT is impossible), /V for specifying the disk volume label, and so on. It also has many undocumented parameters.
MEM displays memory status.
Usage: MEM
It also has quite a few options, such as /C to list the memory usage of all programs, /D to display detailed information such as the status of memory-resident programs and device drivers, /F to display the total amount of free memory, /M to display module information in memory, and /P for paged display. There is also a hidden /A option, which can display HMA information.
MOVE moves files or folders, and can also change the names of files or folders.
Usage: MOVE file1 file2
For example, MOVE C:\*.EXE D:
This command can move all files with the EXE extension in the root folder of drive C to drive D.
XCOPY copies files or folders.
Usage: XCOPY filename1 name2]
It has a great many options, such as /S to copy files in an entire folder (including subfolders), /E to include empty folders, /V to verify the correctness of copied files after copying, /Y to confirm, and so on.
CLS clears the screen.
Usage: CLS
SYS transfers the system, that is, it transfers system files (such as IO.SYS and so on) from one place to the specified drive.
Usage: SYS folder name
For example, SYS C:\DOS A:
This command transfers the system files located in the C:\DOS folder to drive A.
DATE displays or sets the date.
Usage: DATE
TIME displays or sets the time.
Usage: TIME
DOS also comes with some other commands, such as SORT (sorting), FIND (searching for characters), and so on.
Besides the commands that come with DOS, there are also many other enhanced commands that are very practical and can greatly enhance DOS's capabilities. Many of these programs can be downloaded in “DOS Software”.
Essential Tools under DOS
DOS is a very powerful and practical operating system, with the largest number of users. But after installing DOS, we find that the commands included with DOS cannot carry out all the functions everyone needs. At this time, we need some other software to implement those functions. There is a great deal of practical software under DOS, so which tools should we choose from them as essential tools? Below, let's discuss them by category.
After installing the operating system, the first thing is to let the hardware of the whole computer perform its functions, such as the mouse, CD-ROM drive, sound card, and so on. At this time, corresponding drivers are needed, and these drivers are essential tools under DOS. These drivers can be downloaded from the site's “DOS Software”, and for installation and setup methods, please see “Use and setup of hardware devices under DOS” in this section.
After the hardware can all work normally, DOS should be made to complete the needed functions. DOS is not only a convenient and practical operating system, but also a basic operating system. Many interface enhancement programs (such as Windows 3.x/9x) are implemented on its foundation; that is, DOS is their kernel. Therefore, it is very suitable to do some system and disk management under DOS, such as disk copying, partitioning, formatting, and so on. At this time, disk tools such as GHOST, FDISK, FORMAT, and PQMAGIC can show their abilities and can be regarded as essential tools under DOS. Of course, other system maintenance tools (such as disk checking tools and so on) are also very important; everyone can see them in “DOS system maintenance” in this section.
As everyone knows, in order to save space, many files are stored using compression methods. Therefore, tools for compression and extraction under DOS are very important. Common compression formats include ZIP, RAR, and ARJ, and the DOS tools that can create and extract these formats are PK(UN)ZIP, (UN)RAR, and (UN)ARJ respectively. They are all very convenient and fast to use; for example, PKUNZIP *.ZIP can extract all ZIP files in the current folder. The RAR and ARJ formats are the same, and corresponding archives can be created or extracted. But note that because RAR adopted a new RAR compression format in version 3.0 in recent years, many new RAR files must be extracted with the latest version of RAR (that is, version 3.0), which can be downloaded from the site's “Compression Tools”. As for the specific usage of tools such as PKZIP/PKUNZIP and RAR mentioned above, see “Use of common compression and extraction tools under DOS” in the site's “DOS Articles” section. Besides compressing ordinary files, executable files can also be compressed, that is, their size can be reduced. The best compression tool for executable files is UPX. It is very powerful and can be treated as an essential tool.
There are also some files called image files, such as IMG files. Many of them are produced with HD-COPY, though of course there are other tools as well. The best way to extract these files is to use UNDISK (available for download from the site). It can extract image files very efficiently and can be treated as an essential tool. It is best not to use tools such as HD-COPY to extract these files, because this tool is not only old, but can only extract files onto floppies, which is very inconvenient. The UNDISK just mentioned is much easier to use.
Then what if you do not know what compression format some files are in (especially when the extension is lost)? At this time, you can use a very powerful DOS tool called GetType. Its latest version is 2.60 and can be downloaded from the site. It can display in great detail the information in compressed/image/encrypted files, and can even display all of their contents without needing any other software. Not only that, it can also display information in executable files (including Windows files) and other files. It is very powerful and supports long filenames. Everyone can treat it as an essential tool, because once you have it, operation becomes much more convenient.
Everyone knows that Windows File Manager is very intuitive to use. There are also many such tools under DOS, which can be found in the site's “File Management”. They are all operated graphically. Besides basic file management functions, they can usually also perform many other functions, such as coming with a file editor and being able to view the contents of compressed files. In recent years, file management tools under DOS have also added support for long filenames and FAT32. Among these tools, more practical ones include Volkov Commander and so on. Their interfaces are all quite good, and their functions are also strong, so everyone can use them as essential tools.
When using DOS, you will naturally deal with files and folders often, so how to use these files and folders well is very important. Common file operations such as creating, deleting, editing, and so on can be done either with commands that come with DOS or with many enhanced tools, which can greatly improve the efficiency of file operations. These tools can be downloaded from the site's “File Tools”; most of the file tools on the site support long filenames and FAT32 partitions. Pure DOS can usually use only short filenames, so how can it use long filenames? Actually, it is not difficult. Usually there are two methods: long filename drivers and directly operating long filenames. The corresponding tools are DOSLFN/LFNDOS and Odi's LFN tools, which are very practical and can be regarded as essential tools. For specific methods of using long filenames under pure DOS, please see the articles in the site's “DOS Articles” section.
With the development of computers, more and more people have begun to use them, so many everyday tasks (such as writing articles, listening to music, viewing images, and so on) are done on computers. Then how can these operations be carried out under DOS? First, writing articles. DOS comes with an EDIT command, which can edit multiple files and binary files, but its functions are not very powerful (for example, it cannot set fonts and so on), so other specialized word processing tools can be used to do the job. Famous tools of this kind include MS-Word, CCED, WPS, and so on, which can be downloaded in the site's “Text” tools. Some people like to listen to music while typing, and of course this can also be done under DOS. Taking SETEDIT as an example, it is a very powerful and practical DOS word processing program. It not only has word processing functions, but can also play MP3 music while you write. How nice! Therefore, these can also be used as essential tools.
Having finished talking about document processing under DOS, next comes listening to music, viewing images, and so on. There is a great deal of software for listening to music and viewing images under DOS. For example, you can listen to music in WAV, MID, MP3, and other formats, and the functions and effects are very good (definitely not the playback quality of DOSAMP, the oldest and worst MP3 player). Details can be seen in “Multimedia under DOS” in this section. For example, QuickView is very small in size, yet very powerful, and everyone can treat it as an essential tool. Viewing images under DOS is also very convenient, and there are usually two methods: command-line mode and graphical interface mode. Taking PictView (which can be downloaded from the site's “Graphics Software”) as an example, it can display more than 40 image formats, such as JPG, GIF, BMP, TGA, ICO, GIF, and so on. Not only is it fast, with good quality and effect, but it is also very small, only a little over 100K! Therefore, it can absolutely be used as an essential tool. But some image software, especially old image software such as NV, is not only slow and poor in display quality, but also very large, so it is best not to use it.
There is also a lot of very powerful and practical software under DOS that can be used as essential tools. DOS software is usually compact and practical, which naturally makes things much more convenient for everyone. For example, commands such as SHUTDOWN and POWEROFF can easily implement soft power-off under the DOS command-line mode. Not only are they very convenient to use, but they are also very small, so everyone can use them as essential tools. There are also some enhanced DOS command tools that can greatly enhance the functions of DOS's built-in externals, such as XXCOPY, XMSDSK, and so on, which can be downloaded from the site. For everyone's convenience, I made a “Common DOS Tool Collection”, including directly runnable versions of the various kinds of software above (such as command-line tools, drivers, system tools, disk tools, compression tools, multimedia software, and so on), and placed it in “DOS System” under the site's “DOS Software” section. Everyone is welcome to download and use it.
Since each person's habits and interests are different, the main operations each person performs are also different. For example, some people like programming or writing batch files, and can use some practical batch processing tools (which can be downloaded from the site's “Script Tools”) as essential tools; some people like playing games, and can use some game modification software or emulators (which can be downloaded from the site's “Game Software”) as essential tools. Therefore, everyone can also choose essential tools suitable for themselves according to their own preferences. However, everyone should try to use DOS software released in recent years, because these programs are not only stronger overall in function, but also support the latest computer technologies (such as FAT32 partitions, large hard disks, long filenames, PCI/USB devices, and so on). In short, as long as we are good at choosing and using DOS software, we can make DOS very powerful and let DOS bring out its proper functions.
Common Error Messages at the DOS Command Line
While using DOS, everyone often encounters some error messages at the command line. Since they are often in English, some people do not know what is going on when they see them, much less how to solve them. Below, I will introduce some common error messages in DOS command-line mode.
Bad command or file name
Wrong command or filename
Cause of error and solution:
This is probably the error prompt everyone sees most often. It means the entered command is invalid. If the command entered is neither a DOS internal command, nor can the system find the corresponding executable file in the search path or specified path, this error message will appear. You can check whether the command you entered is correct, such as whether you typed a letter wrong.
Access Denied
Access denied
Cause of error and solution:
This is also a common error, and it appears in many situations, such as when using the DEL command to delete a file with the read-only attribute, when multiple processes in a multitasking environment access the same file at the same time, or when trying to write a file into a network folder with read-only permission. The solution is also simple: just remove the file's read-only, hidden, and other attributes, or make sure only one process is reading and writing the file at the same time, and remove the network folder's read-only permission.
Drive not ready
Drive not ready
Cause of error and solution:
Surely everyone has run into this error message! It is especially common when accessing removable disks (including floppy disks and CDs). The solution is to insert the disk properly and then try again.
Write protect error
Write protection error
Cause of error and solution:
This error appears when trying to write information to a write-protected disk (usually a floppy disk). Just remove the disk's write protection.
General error
General error
Cause of error and solution:
This error usually appears when DOS cannot recognize the format of the specified disk, such as when a floppy disk is unformatted. Format the disk with commands such as FORMAT, or convert it to a format DOS can recognize.
Abort,Retry,Ignore,Fail?
Abort, retry, ignore, fail?
Cause of error and solution:
This error message appears very frequently, for example when the disk is not ready. Entering A cancels the operation and then returns to the DOS prompt; entering R means try again; entering I means ignore this error and continue, which is best not used; entering F means skip this error, and this option is often chosen.
File not found
File not found
Cause of error and solution:
This prompt appears when many commands cannot find the specified file. For example, when using the DIR command, if the specified file does not exist, this error message will appear. The solution is to enter the filename correctly.
Incorrect DOS version
Incorrect DOS version
Cause of error and solution:
This error message appears when a command to be executed finds that the current DOS version is not the same as the DOS version expected by that command. For details and solutions, please see the article in the site's “DOS Articles” section.
Invalid directory
Invalid directory
Cause of error and solution:
This prompt appears if you enter a nonexistent or invalid directory. You can check whether the input was wrong.
Invalid Drive Specification
Invalid drive specification
Cause of error and solution:
This prompt appears when the entered drive does not exist. Please check whether that drive exists. Some drives (such as NTFS volumes, CD-ROM drives, network drives, and so on) require the corresponding drivers to be loaded before they can be recognized.
Syntax error
Syntax error
Cause of error and solution:
This message is fairly common when using some batch commands (such as IF, FOR, and so on). You can check whether you entered invalid syntax. Taking the FOR command as an example, its syntax is FOR %F IN (文件名) DO 命令. You must not get this syntax format wrong (such as reversing it or leaving something out); you must enter the correct command to get the corresponding result.
Required parameter missing
Missing required parameter
Cause of error and solution:
If, when executing a command (such as DEL), you leave out a parameter needed for it to complete its function normally, this prompt will appear.
Invalid parameter
Invalid parameter
Cause of error and solution:
This appears when an invalid parameter is entered while executing a command. You can check whether the entered parameter is correct, whether there are spelling mistakes, and so on. If you do not know what parameters there are, you can usually use the /? option of the command to view the parameter list.
Not enough memory 或 Insufficient memory
Not enough memory
Cause of error and solution:
If, when executing a program, the program finds that the memory it requires is greater than the memory available for use (usually meaning conventional memory), this message will appear. Situations that cause insufficient memory include having executed too many or overly large memory-resident programs, or the system memory not having been configured well. Everyone can see “Memory configuration under DOS” in this section.
Divide overflow 或 Divide by zero
Divisor is zero
Cause of error and solution:
If a program is run when the system is unstable, in conflict with other programs, or when the program itself has problems, this error can appear. You can try restarting the system and then running the program again.
Runtime error xxx
Runtime error xxx
Cause of error and solution:
This is similar to the above “Divisor is zero” error. If the value of xxx is 200, see the “DOS Articles” section.
Error in EXE file
Error in EXE file
Cause of error and solution:
Usually this means the executable file is already damaged and can no longer be used. Just use a good one.
The above are common error messages in DOS command-line mode. Everyone can use the above text to troubleshoot problems.
Common DOS Commands Essential Tools under DOS Common Error Messages at the DOS Command Line
Multimedia under DOS Ways to network under DOS Use and setup of hardware devices under DOS
DOS system maintenance Memory configuration under DOS Commands and configuration of the CONFIG.SYS file
DOS batch files Undocumented DOS commands and parameters
Common DOS Commands
If you want to operate and use DOS, knowing some common commands is very important. Below are the uses of some commands.
A filename is made up of the file path and the filename together, such as C:\DOS\COMMAND.COM.
DIR displays files and folders (directories).
Usage: DIR
It has many options, such as /A meaning display all files (including those with hidden and system attributes), /S meaning also display files in subfolders, /P meaning paged display, /B meaning display filenames only, and so on.
For example, DIR A*.EXE /A /P
This command displays, page by page, all files (folders) in the current folder whose names start with A and whose extension is EXE.
CD or CHDIR changes the current folder.
Usage: CD
If no folder name is given, it displays the current path.
MD or MKDIR creates a folder.
Usage: MD folder name
RD or RMDIR deletes a folder.
Usage: RD folder name
Note: this folder must be empty.
DEL or ERASE deletes files.
Usage: DEL/ERASE filename
COPY copies files.
Usage: COPY filename1
For example, COPY /B A+B C
This command combines the two binary files A and B into one file C.
TYPE displays file contents.
Usage: TYPE filename
REN or RENAME changes a filename; in DOS7 it can also change a folder name.
Usage: REN file(folder)name1 file(folder)name2
EDIT edits files; in DOS7 it can also edit binary files.
Usage: EDIT
For example, EDIT /70 C:\COMMAND.COM
This command edits the file C:\COMMAND.COM in binary mode.
FORMAT formats a disk.
Usage: FORMAT drive
It has many options, such as /Q for quick format, /U for unconditional format (that is, recovery with commands like UNFORMAT is impossible), /V for specifying the disk volume label, and so on. It also has many undocumented parameters.
MEM displays memory status.
Usage: MEM
It also has quite a few options, such as /C to list the memory usage of all programs, /D to display detailed information such as the status of memory-resident programs and device drivers, /F to display the total amount of free memory, /M to display module information in memory, and /P for paged display. There is also a hidden /A option, which can display HMA information.
MOVE moves files or folders, and can also change the names of files or folders.
Usage: MOVE file1 file2
For example, MOVE C:\*.EXE D:
This command can move all files with the EXE extension in the root folder of drive C to drive D.
XCOPY copies files or folders.
Usage: XCOPY filename1 name2]
It has a great many options, such as /S to copy files in an entire folder (including subfolders), /E to include empty folders, /V to verify the correctness of copied files after copying, /Y to confirm, and so on.
CLS clears the screen.
Usage: CLS
SYS transfers the system, that is, it transfers system files (such as IO.SYS and so on) from one place to the specified drive.
Usage: SYS folder name
For example, SYS C:\DOS A:
This command transfers the system files located in the C:\DOS folder to drive A.
DATE displays or sets the date.
Usage: DATE
TIME displays or sets the time.
Usage: TIME
DOS also comes with some other commands, such as SORT (sorting), FIND (searching for characters), and so on.
Besides the commands that come with DOS, there are also many other enhanced commands that are very practical and can greatly enhance DOS's capabilities. Many of these programs can be downloaded in “DOS Software”.
Essential Tools under DOS
DOS is a very powerful and practical operating system, with the largest number of users. But after installing DOS, we find that the commands included with DOS cannot carry out all the functions everyone needs. At this time, we need some other software to implement those functions. There is a great deal of practical software under DOS, so which tools should we choose from them as essential tools? Below, let's discuss them by category.
After installing the operating system, the first thing is to let the hardware of the whole computer perform its functions, such as the mouse, CD-ROM drive, sound card, and so on. At this time, corresponding drivers are needed, and these drivers are essential tools under DOS. These drivers can be downloaded from the site's “DOS Software”, and for installation and setup methods, please see “Use and setup of hardware devices under DOS” in this section.
After the hardware can all work normally, DOS should be made to complete the needed functions. DOS is not only a convenient and practical operating system, but also a basic operating system. Many interface enhancement programs (such as Windows 3.x/9x) are implemented on its foundation; that is, DOS is their kernel. Therefore, it is very suitable to do some system and disk management under DOS, such as disk copying, partitioning, formatting, and so on. At this time, disk tools such as GHOST, FDISK, FORMAT, and PQMAGIC can show their abilities and can be regarded as essential tools under DOS. Of course, other system maintenance tools (such as disk checking tools and so on) are also very important; everyone can see them in “DOS system maintenance” in this section.
As everyone knows, in order to save space, many files are stored using compression methods. Therefore, tools for compression and extraction under DOS are very important. Common compression formats include ZIP, RAR, and ARJ, and the DOS tools that can create and extract these formats are PK(UN)ZIP, (UN)RAR, and (UN)ARJ respectively. They are all very convenient and fast to use; for example, PKUNZIP *.ZIP can extract all ZIP files in the current folder. The RAR and ARJ formats are the same, and corresponding archives can be created or extracted. But note that because RAR adopted a new RAR compression format in version 3.0 in recent years, many new RAR files must be extracted with the latest version of RAR (that is, version 3.0), which can be downloaded from the site's “Compression Tools”. As for the specific usage of tools such as PKZIP/PKUNZIP and RAR mentioned above, see “Use of common compression and extraction tools under DOS” in the site's “DOS Articles” section. Besides compressing ordinary files, executable files can also be compressed, that is, their size can be reduced. The best compression tool for executable files is UPX. It is very powerful and can be treated as an essential tool.
There are also some files called image files, such as IMG files. Many of them are produced with HD-COPY, though of course there are other tools as well. The best way to extract these files is to use UNDISK (available for download from the site). It can extract image files very efficiently and can be treated as an essential tool. It is best not to use tools such as HD-COPY to extract these files, because this tool is not only old, but can only extract files onto floppies, which is very inconvenient. The UNDISK just mentioned is much easier to use.
Then what if you do not know what compression format some files are in (especially when the extension is lost)? At this time, you can use a very powerful DOS tool called GetType. Its latest version is 2.60 and can be downloaded from the site. It can display in great detail the information in compressed/image/encrypted files, and can even display all of their contents without needing any other software. Not only that, it can also display information in executable files (including Windows files) and other files. It is very powerful and supports long filenames. Everyone can treat it as an essential tool, because once you have it, operation becomes much more convenient.
Everyone knows that Windows File Manager is very intuitive to use. There are also many such tools under DOS, which can be found in the site's “File Management”. They are all operated graphically. Besides basic file management functions, they can usually also perform many other functions, such as coming with a file editor and being able to view the contents of compressed files. In recent years, file management tools under DOS have also added support for long filenames and FAT32. Among these tools, more practical ones include Volkov Commander and so on. Their interfaces are all quite good, and their functions are also strong, so everyone can use them as essential tools.
When using DOS, you will naturally deal with files and folders often, so how to use these files and folders well is very important. Common file operations such as creating, deleting, editing, and so on can be done either with commands that come with DOS or with many enhanced tools, which can greatly improve the efficiency of file operations. These tools can be downloaded from the site's “File Tools”; most of the file tools on the site support long filenames and FAT32 partitions. Pure DOS can usually use only short filenames, so how can it use long filenames? Actually, it is not difficult. Usually there are two methods: long filename drivers and directly operating long filenames. The corresponding tools are DOSLFN/LFNDOS and Odi's LFN tools, which are very practical and can be regarded as essential tools. For specific methods of using long filenames under pure DOS, please see the articles in the site's “DOS Articles” section.
With the development of computers, more and more people have begun to use them, so many everyday tasks (such as writing articles, listening to music, viewing images, and so on) are done on computers. Then how can these operations be carried out under DOS? First, writing articles. DOS comes with an EDIT command, which can edit multiple files and binary files, but its functions are not very powerful (for example, it cannot set fonts and so on), so other specialized word processing tools can be used to do the job. Famous tools of this kind include MS-Word, CCED, WPS, and so on, which can be downloaded in the site's “Text” tools. Some people like to listen to music while typing, and of course this can also be done under DOS. Taking SETEDIT as an example, it is a very powerful and practical DOS word processing program. It not only has word processing functions, but can also play MP3 music while you write. How nice! Therefore, these can also be used as essential tools.
Having finished talking about document processing under DOS, next comes listening to music, viewing images, and so on. There is a great deal of software for listening to music and viewing images under DOS. For example, you can listen to music in WAV, MID, MP3, and other formats, and the functions and effects are very good (definitely not the playback quality of DOSAMP, the oldest and worst MP3 player). Details can be seen in “Multimedia under DOS” in this section. For example, QuickView is very small in size, yet very powerful, and everyone can treat it as an essential tool. Viewing images under DOS is also very convenient, and there are usually two methods: command-line mode and graphical interface mode. Taking PictView (which can be downloaded from the site's “Graphics Software”) as an example, it can display more than 40 image formats, such as JPG, GIF, BMP, TGA, ICO, GIF, and so on. Not only is it fast, with good quality and effect, but it is also very small, only a little over 100K! Therefore, it can absolutely be used as an essential tool. But some image software, especially old image software such as NV, is not only slow and poor in display quality, but also very large, so it is best not to use it.
There is also a lot of very powerful and practical software under DOS that can be used as essential tools. DOS software is usually compact and practical, which naturally makes things much more convenient for everyone. For example, commands such as SHUTDOWN and POWEROFF can easily implement soft power-off under the DOS command-line mode. Not only are they very convenient to use, but they are also very small, so everyone can use them as essential tools. There are also some enhanced DOS command tools that can greatly enhance the functions of DOS's built-in externals, such as XXCOPY, XMSDSK, and so on, which can be downloaded from the site. For everyone's convenience, I made a “Common DOS Tool Collection”, including directly runnable versions of the various kinds of software above (such as command-line tools, drivers, system tools, disk tools, compression tools, multimedia software, and so on), and placed it in “DOS System” under the site's “DOS Software” section. Everyone is welcome to download and use it.
Since each person's habits and interests are different, the main operations each person performs are also different. For example, some people like programming or writing batch files, and can use some practical batch processing tools (which can be downloaded from the site's “Script Tools”) as essential tools; some people like playing games, and can use some game modification software or emulators (which can be downloaded from the site's “Game Software”) as essential tools. Therefore, everyone can also choose essential tools suitable for themselves according to their own preferences. However, everyone should try to use DOS software released in recent years, because these programs are not only stronger overall in function, but also support the latest computer technologies (such as FAT32 partitions, large hard disks, long filenames, PCI/USB devices, and so on). In short, as long as we are good at choosing and using DOS software, we can make DOS very powerful and let DOS bring out its proper functions.
Common Error Messages at the DOS Command Line
While using DOS, everyone often encounters some error messages at the command line. Since they are often in English, some people do not know what is going on when they see them, much less how to solve them. Below, I will introduce some common error messages in DOS command-line mode.
Bad command or file name
Wrong command or filename
Cause of error and solution:
This is probably the error prompt everyone sees most often. It means the entered command is invalid. If the command entered is neither a DOS internal command, nor can the system find the corresponding executable file in the search path or specified path, this error message will appear. You can check whether the command you entered is correct, such as whether you typed a letter wrong.
Access Denied
Access denied
Cause of error and solution:
This is also a common error, and it appears in many situations, such as when using the DEL command to delete a file with the read-only attribute, when multiple processes in a multitasking environment access the same file at the same time, or when trying to write a file into a network folder with read-only permission. The solution is also simple: just remove the file's read-only, hidden, and other attributes, or make sure only one process is reading and writing the file at the same time, and remove the network folder's read-only permission.
Drive not ready
Drive not ready
Cause of error and solution:
Surely everyone has run into this error message! It is especially common when accessing removable disks (including floppy disks and CDs). The solution is to insert the disk properly and then try again.
Write protect error
Write protection error
Cause of error and solution:
This error appears when trying to write information to a write-protected disk (usually a floppy disk). Just remove the disk's write protection.
General error
General error
Cause of error and solution:
This error usually appears when DOS cannot recognize the format of the specified disk, such as when a floppy disk is unformatted. Format the disk with commands such as FORMAT, or convert it to a format DOS can recognize.
Abort,Retry,Ignore,Fail?
Abort, retry, ignore, fail?
Cause of error and solution:
This error message appears very frequently, for example when the disk is not ready. Entering A cancels the operation and then returns to the DOS prompt; entering R means try again; entering I means ignore this error and continue, which is best not used; entering F means skip this error, and this option is often chosen.
File not found
File not found
Cause of error and solution:
This prompt appears when many commands cannot find the specified file. For example, when using the DIR command, if the specified file does not exist, this error message will appear. The solution is to enter the filename correctly.
Incorrect DOS version
Incorrect DOS version
Cause of error and solution:
This error message appears when a command to be executed finds that the current DOS version is not the same as the DOS version expected by that command. For details and solutions, please see the article in the site's “DOS Articles” section.
Invalid directory
Invalid directory
Cause of error and solution:
This prompt appears if you enter a nonexistent or invalid directory. You can check whether the input was wrong.
Invalid Drive Specification
Invalid drive specification
Cause of error and solution:
This prompt appears when the entered drive does not exist. Please check whether that drive exists. Some drives (such as NTFS volumes, CD-ROM drives, network drives, and so on) require the corresponding drivers to be loaded before they can be recognized.
Syntax error
Syntax error
Cause of error and solution:
This message is fairly common when using some batch commands (such as IF, FOR, and so on). You can check whether you entered invalid syntax. Taking the FOR command as an example, its syntax is FOR %F IN (文件名) DO 命令. You must not get this syntax format wrong (such as reversing it or leaving something out); you must enter the correct command to get the corresponding result.
Required parameter missing
Missing required parameter
Cause of error and solution:
If, when executing a command (such as DEL), you leave out a parameter needed for it to complete its function normally, this prompt will appear.
Invalid parameter
Invalid parameter
Cause of error and solution:
This appears when an invalid parameter is entered while executing a command. You can check whether the entered parameter is correct, whether there are spelling mistakes, and so on. If you do not know what parameters there are, you can usually use the /? option of the command to view the parameter list.
Not enough memory 或 Insufficient memory
Not enough memory
Cause of error and solution:
If, when executing a program, the program finds that the memory it requires is greater than the memory available for use (usually meaning conventional memory), this message will appear. Situations that cause insufficient memory include having executed too many or overly large memory-resident programs, or the system memory not having been configured well. Everyone can see “Memory configuration under DOS” in this section.
Divide overflow 或 Divide by zero
Divisor is zero
Cause of error and solution:
If a program is run when the system is unstable, in conflict with other programs, or when the program itself has problems, this error can appear. You can try restarting the system and then running the program again.
Runtime error xxx
Runtime error xxx
Cause of error and solution:
This is similar to the above “Divisor is zero” error. If the value of xxx is 200, see the “DOS Articles” section.
Error in EXE file
Error in EXE file
Cause of error and solution:
Usually this means the executable file is already damaged and can no longer be used. Just use a good one.
The above are common error messages in DOS command-line mode. Everyone can use the above text to troubleshoot problems.