Installation Problem

On installation you receive a message similar to:-

16-bit MS-DOS Subsystem
path to the program that you are trying to start or install
C:\Windows\System32\Autoexec.nt The system file is not suitable for running MS-DOS and Microsoft Windows applications. Choose 'Close' to terminate the application.

This appears to be caused by missing or damaged file possibly caused by a trojan or virus. Look at the Microsoft Knowledge Base for guidance.