CD-ROM Windows XP Fix

Installation of The Code Book on CD-ROM fails on certain computers running Windows XP. This page explains how to fix the problem.

Installation fails with Windows XP

When: This problem occasionally occurs with Windows XP. Most users experience no problems.

What: An error message such as “The system file is not suitable for running MS-DOS and Microsoft Windows applications” is displayed.

Why: One or more files are missing and must be replaced.

How: Follow these step-by-step instructions:

  1. Insert your Windows XP CD-ROM into your CD or DVD drive
  2. Open “My Computer” to find out the drive letter for the drive you are using. This will be in brackets after the name of the CD-ROM, e.g. (D:).
  3. Click the Start button in the bottom left of your screen and then click Run.
  4. In the Open box, type cmd and then click OK.
    1. expand DrvLett:\i386\config.nt_ c:\windows\system32\config.nt
    2. expand DrvLett:\i386\autoexec.nt_ c:\windows\system32\autoexec.nt
    3. expand DrvLett:\i386\command.co_ c:\windows\system32\command.com
    4. exit
  5. At the command prompt, type the following commands, pressing ENTER after each one, and replacing DrvLett with the drive letter you found in step 2.
    Note that there are two spaces in each of the first 3 commands, one after “expand” and one after the underscore symbol “_”.
  6. Now try using The Code Book on CD-ROM. If everything works correctly you should not proceed any further with these instructions.
  7. If and only if the problem is not fixed, you should start up “Notepad” on your computer, then go to this Microsoft Help Page and start following the instructions from instruction number 7 on that page.