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DOS疑难解答 & 问题讨论（解答室） » Please, experts, give me some pointers—I really can't figure this problem out.

Floor1　yflyl	Posted 2003-02-01 00:00
初级用户　Posts 7　Credits 135
I made a pqmagic image file for an EasyBoot boot menu. The resulting CD image file iso runs perfectly normally in Virtual PC, but after burning it to a CD and running it, this problem appears (system message: Not enough drive letters available invalid drive specification). I looked carefully at Autoexec.bat and config.sys but couldn't see any problem, so I have no choice but to ask the experts for help. The contents of the two files are as follows: Autoexec.bat @ECHO OFF MSCDEX.EXE /D:mscd001 /L:Z Z:\SOFT\PQMAGIC\MOUSE.COM Z:\SOFT\PQMAGIC\PQMAGIC.EXE config.sys device=himem.sys /testmemff device=oakcdrom.sys /D:mscd001 files=20 buffers=20 dos=high,umb stacks=9,256 lastdrive=z

Floor2　MYS	Posted 2003-02-01 00:00
元老会员　Posts 1,637　Credits 5,170　From 广东佛山
Not enough drive letters available invalid drive specification definitely means there aren't enough drive letters. I suspect the “lastdrive=z” in config.sys is wrong. Please check carefully.

Floor3　yflyl	Posted 2003-02-02 00:00
初级用户　Posts 7　Credits 135
It's already defined as the last drive letter, so how can it still not be enough? That's exactly the part I don't understand.

Floor4　Wengier	Posted 2003-02-02 00:00
系统支持　Posts 10,521　Credits 27,736
Which command gives those error messages? I guess it's caused by assigning the CD drive letter to Z. Try moving it forward a bit, for example MSCDEX /D:xxx /L:K, or just MSCDEX /D:xxx directly. Or you can also increase the final drive letter specified by LASTDRIVE further, for example: LASTDRIVE=32 to specify the maximum number of drive letters as 32, instead of Z (Z means 26). Note: “LASTDRIVE=number” is an undocumented DOS usage, only for MS-DOS 7.x or DR-DOS. In that case, 6 more drives can be accessed, namely: : ^: _: `: Actually, this usage also works in Win2K, for example: SUBST ^: C:\TEMP, and then the ^ drive can be redirected to the C:\TEMP folder.

Floor5　yflyl	Posted 2003-02-02 00:00
初级用户　Posts 7　Credits 135
Really good, worthy of being the super moderator. Many thanks. I'll give it a try.

Floor6　ko20010214	Posted 2003-07-04 00:00
版主　Posts 1,628　Credits 7,296
Learn how to ask a question first. Change your post title to something better. From now on, posts with titles like this may end up with only these three fates: 1。No one pays any attention. (This is the best-case scenario) 2。Moved to the off-topic section. 3。Deleted.