There are dozens of posts with that same plea in the forums. If you used the forum search you could have saved yourself time making (yet another) post about this issue.
Look up AUTOEXEC.NT or FIXXP in the Forum search if you need more info.
In closing, why did you pick such a slow forum? Your question seems offtopic, but welcome.
Bob
I keep getting this error when I try to install any program. I have read the other topics on fixing but non have worked for me. DOSX.EXE is in my C:\WINDOWS\SYSTEM32\DOSX.EXE and AUTOEXEC.NT in is C:\WINDOWS\AUTOEXEC.NT and CONFIG.NT is in my C:\WINDOWS\CONFIG.NT. I have never touched these files. Please someone help me out here. Thanks!
OS:Windows XP
COMPUTER: Dell

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