Solution?
The easiest is simply inserting the Windows XP CD into the CD drive and clicking start --> Run and entering:
expand X:\i386\autoexec.nt_ c:\windows\system32\autoexec.nt
Replace X:\ with your CD ROM drive letter.
Microsoft has provided a solution for this problem here. It is related to running DOS based or 16 bit applications in Windows XP. If you either do not have this CD for some reason try downloading it here. After downloading the .zip you will have to extract it to your windows\system32 directory. If this file does not work properly for you please check the feedback thread for assistance on your specific version of windows.