### 1. Description of Incorrect Solutions
When you forget the administrator password while using Windows XP, what should you do? There is a popular method on the Internet: Use a DOS boot disk (if the partition where Windows XP is located is an NTFS partition, a DOS boot disk that supports NTFS is needed) to enter real-mode DOS, and delete a file named sam in the %SystemRoot%system32config directory. Restart the system, the login password of Administrator is empty, and we can easily log in to the system.
**Small Knowledge**: In Windows NT/2000/XP, the management of user accounts adopts the mechanism of the Security Account Manager (SAM). This mechanism does not manage accounts by directly confirming the username and password form, but by the security identifier (SID). The SID is created at the same time when the account is created. Once the account is deleted, the SID is also deleted. The SID information of the system is saved in the %SystemRoot%system32configsam file in the form of "SID s-1-5-21-xxxxxxxxxxxxxx-xxxxxxxxxxxxxx-005".
### 2. Origin and Consequences of the Scheme
This incorrect method comes from the previous way of handling the forgotten password in Windows 2000. Users of Windows 2000 (without installing Service Pack) can use this method to successfully crack the login password. The theoretical support of this scheme is: The password of Windows XP is stored in the sam file. When we log in to the system, the system will automatically verify the sam database information. If the password and username this time match the encrypted data in the sam file, the system will log in successfully. Otherwise, it cannot log in. If this file is deleted, the sam database will be cleared, and the login password of the administrator will also be cleared, naturally avoiding the login password verification mechanism of Windows XP.
In fact, this method is already invalid for Windows 2000 SP1-SP4, and is completely useless for Windows XP. If everyone operates on Windows XP according to this scheme, a situation of being unable to start will occur, bringing greater trouble to our operation.
### 3. Correct Solutions:
When the login password of Windows XP is lost, we can adopt different methods to solve it according to different situations:
(1) If when installing Windows XP, the Administrator password is set to empty. Everyone can press F8 to enter the safe mode when the system is booting. The Administrator password here is empty, and we can directly enter. After entering, we can set the account and password.
(2) If the Administrator password is set, the cracking method is not that simple. We can use the super-strong Windows 2000/XP system maintenance CD - ERD Commander 2003. After booting the system with this CD, run the command "Start → Management → Tools → Password Modification" to open the "ERD Commander 2003 LockSmith Wizard" window. Enter the account name to be cracked in the "Account" box, and then enter the new password. It's ok.
**Small Tips**:
★ERD Commander is shareware. Its official homepage is:
www.winternals.com/
The download address of the ISO file of the Chinese version of ERD Commander 2003 is:
soft.0zones.com/SoftDown.asp?ID=21081