FABS - Qbasic

[mnrvovrfc]

By the way, I don't know how to attach the program FABS.COM to a post

Oh I'm sorry, didn't see OP's post on second page saying he was on Windows7 32-bit but anyway...

In my experience, running a 16-bit executable file is blocked by Windows10. I tried to run QB.EXE (M$ QuickBasic v4.5) executable once on one of my computers and got one of the fancy cheap dialogs that the OS was unwilling. If it refuses to run a 16-bit EXE file then it would certainly reject a COM file, that's why COMMAND.COM was removed from the OS (and on QB64 as late as v0.98 the code for "SHELL" was still checking for its existence). This probably applies to Windows8 as well.

Loading a Quick Library might be part of the problem, and have to be careful all filenames are 8-dot-3 without spaces because that was 16-bit MS-DOS limitation.

For Vista+ the creators began making it difficult to use MS-DOS apps, maybe making changes to the Windows API, also User Account Control became involved (many things in the past have to be run as administrator which sucked). Might have to go looking for an emulator only so the COM file runs.

EDIT: You might want to look at Freebasic, but read extensively about the MS-DOS mod because it requires a lot of crazy stuff only to make programs created by a 32-bit compiler pretend they are 16-bit. If your BASIC code is straight out of QuickBasic, it might be compiled in "-lang qb" mode without a lot of modifications.