AUTOEXEC.NT, CONFIG.NT - The system file is not suitable for running MS-DOS and Microsoft Windows applications

Problem

You start to install Office 97 or run some other program for the first time and get the following message:

C:\Windows\System32\AUTOEXEC.NT.  
The system file is not suitable for running MS-DOS and Microsoft Windows applications.  
Choose 'Close' to terminate this application.

Solution

This Microsoft article describes the problem in detail

The quick version:

If you run into this or similar "WOW DVM" errors when running a 16-bit program (and the Office 97 installer is 16-bit, though the program itself is 32-bit) it's because one of the following files is missing from \Windows\System32:

• Config.nt
• Autoexec.nt
• Command.com

Check to see that these files are there. If not, expand them from the Windows installation CD and copy them to \Windows\System32. They'll be in the \I386 folder as

Config.nt_
autoexec.nt_
command.co_

You'll need to use the Expand program to convert these to usable form. From a command prompt window, type

Expand /?

to get instructions for using Expand