Computer Software for Steel Professionals

Autoexec.nt Problems

After installing Windows XP Service Pack 2, it is possible that Structural Material Manager's DOS-based subprograms will no longer function. If your PC has this problem, you will see the following error when attempting to use certain Structural Material Manager functions: "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 is not due to any sort of error or XP-incompatibility in the Structural Material Manager software. The problem results from the fact that the setup program for Service Pack 2 can corrupt the autoexec.nt file. Fortunately, the situation can be resolved in any one of several manners.

The easiest fix involves replacing autoexec.nt with an older, known-good copy. The procedures for doing so are presented below. Note that the steps assume that Windows XP is located in a C:\Windows directory; if not, you'll need to substitute the appropriate drive letter and directory name. Attempt the repair as follows:

  1. Browse the C:\Windows\Repair folder. One way to do this is to right-click (not left-click) the Start button to display a pop-up menu. Left-click on the Explore option that appears in that menu, and browse the C: drive. Double-click the Windows folder to open it, and double-click the Repair folder to open it.
  2. Windows Explorer splits the screen into two frames. On the right-hand frame, scroll down to until you find the autoexec.nt file.
  3. Right-click (not left-click) the autoexec.nt file, and select Copy from the pop-up menu that appears.
  4. Just as you browsed to open C:\Windows\Repair in the first step, now browse to open C:\Windows\System32 instead. With the C:\Windows\System32 folder open, right-click somewhere in the right hand frame of Windows Explorer, and select Paste from the pop-up menu. You may be asked for confirmation before overwriting an existing autoexec.nt file, and you definitely want to allow the overwrite.
  5. Close Windows Explorer and all running programs.
  6. Re-start the computer.
  7. Test Structural Material Manager. To do so, open the program, and move past the title screen. Open any job. Now click Material List | Enter / Edit Material. If the blue and white material entry screen properly appears, the problem is solved.

If the above steps did not solve the problem, you should refer to Microsoft's own Web site for other procedures. Microsoft is aware of the problem and presents their own repair instructions at the following link:;en-us;324767#kb4