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How to fix the DOSX.EXE error message?


When I try to open specific programs an error window pops up and says " win 16 subsystem was unable to enter Protected Mode, DOSX.EXE must be in your AUTOEXEC.NT and present in your PATH". How do i fix this problem?


This question was answered on February 10, 2003. Much of the information contained herein may have changed since posting.

Try to do this:

Edit the config.nt file in the C:\windows\system32 directory to read:

EMM = B=4000 RAM

dos=high, umb



Note the spaces in the EMM line carefully - one either side of the first = and before RAM, none with the second =

Also make sure there is a line in your autoexec.nt file (C:\windows\system32 directory) that reads:

lh %SystemRoot%\system32\dosx

I hope that this works.

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Posted by Suzana of Katharine Gibbs School - New York on February 10, 2003