Dealing with older applications on Windows 7, especially when it comes to 16-bit programs, can be quite challenging, but let’s see if we can find a way around this. The error message you're encountering, "NTVDM CPU has encountered an illegal instruction," is a relatively common problem when running 16-bit applications on a 32-bit Windows system.
First, I would suggest confirming that you're indeed on a 32-bit version of Windows 7, as NTVDM isn't present in the 64-bit versions at all. If you're using a 64-bit version, you won't be able to run 16-bit applications directly on Windows 7. Here's what you can try if you are on a 32-bit system:
Reinstall or Repair the Application: If possible, try reinstalling the program. Sometimes files needed by NTVDM may have been corrupted or misplaced.
NTVDM Configuration: Occasionally, some settings within NTVDM itself may need adjustment. You might look into the NTVDM settings or modify how memory is handled by the program. There isn't a direct graphical interface for NTVDM, but you might find settings for the DOS environment in the Properties menu when you right-click the executable file.
Command Prompt Check: Moreover, running a simplified command might help. If there’s a specific line or command that triggers the issue, you could attempt to run the application from the Command Prompt with administrative privileges to see if the response changes.
Consider a Virtual Machine: Since compatibility modes haven’t worked, using a virtual machine could be a reliable solution. Tools like VMware Player or Oracle's VirtualBox are great for setting up an older Windows XP environment where 16-bit support is more robust.
DosBox Emulator: If your application is DOS-based, DosBox is a fantastic tool. It's designed to run DOS programs on modern systems, which might resolve the NTVDM issues entirely.
Running 16-bit applications on newer systems will only get more difficult as Microsoft continues to phase out older technologies, so exploring modern alternatives or updates for your application is a good step forward if available.
Have you had any luck with other methods, like using compatibility layers or third-party tools? If you've discovered partial solutions or specific problems with the above, I’d love to help dig deeper into those aspects. Feel free to update here!
