Problem:
When you boot your machine on error message appears on the screen entitled “16-bit MS-DOS subsystem error” with the path C:\Windows\System32\autoexec.nt indicated in the message. You try to close or ignore the message but it keeps coming back.

Reason:
There are two reasons for this problem. First, the autoexec.nt file could be missing or corrupt. Second, a program could be writing to autoexec.nt causing it to be unreadable.

Solution:
Re-copy autoexec.nt file to System32 folder and make it read-only.

Instructions:

1. Go to the Start menu and select “Run”.
2. In the white box remove any text that may be there and type in “\\Fileshare-nt” and click “OK”.
3. A new window will appear. Double click on Departmental, then Information Systems and Services, Public, Software Error Fixes, Autoexec.nt Error Fix. In this window, you will see two files. One is for Windows 2000 and one is for Windows XP.
4. Double click on the one that you need (If you have windows 2000 then double click on 2000autoexecfix, If you have Windows XP then double click on xpautoexecfix). The error messages should not return.