One question and one suggestion.

Are you running the 64 bit Windows? CoinOPS Diamonds runs MAME64, which would give you a similar result to what you have on a 32 bit system. The fix is pretty easy.

Otherwise, run CoinOPS Diamonds and (try to) run one arcade game, then exit CoinOPS. A text file called “log.txt” is created in the root folder detailing everything CoinOPS does from start up to exiting. The last few lines of the file will show the game you tried to run, and the results of that attempt. This might give you a clue as to what is going on.

I downloaded CoinOPS Diamonds from the torrent here at Arcade Punks and Windows Defender reports it as being clean, and it runs fine. Since it runs just RetroFE and MAME, there shouldn’t be anything that would flag any anti virus app.

It looks like the RetroFE side is running okay for you, but MAME fails. Try running “MAME64.exe” in the coinOPS “emulators” by itself. Just double click it, MAME has a built-in interface.

Check what your Windows version is by selecting “System” and “About” in the Windows Settings, your Windows system type will show up under “Device specifications”. I assume you are running Windows 10.

Every fairly recent Windows computer is 64 bit (Microsoft stopped selling Windows 32 in May), but if you are using an older computer for a retro gaming system or cabinet, there is a chance it is 32 bits. Not to worry, though, as CoinOPS Diamonds includes both the 32 and 64 bit versions of MAME. The 32 bit one is called “MAME.exe” and “MAME64.exe” is 64 bits. Try running “MAME.exe” directly by just double clicking, it has a build in interface. If it runs, your fix is this:

Edit the file “mame.conf” located in the “launchers.windows” folder. This is a text file that tells RetroFE how to run the games. Every emulator has one of these files, which directs your game selection from CoinOPS to the proper emulation folder and program. The MAME launcher contains this:

executable = emulators\MAME\mame64.exe
arguments = “%ITEM_NAME%”

This points to the 64 bit version of MAME. To change this to the 32 bit version (if running “MAME.exe” by itself works for you) to this:

executable = emulators\MAME\mame.exe
arguments = “%ITEM_NAME%”

Note that the only change is the removal of “64”. It is always a good idea to make a copy of the original file before you make any changes. Use the Windows Notepad program to edit. (Or download “Notepad++”, a *much* better editor, and FREE!) Be warned that doing this alteration will change the Official CoinOPS setup and future add-ons might not work.

Remember this will only work if your system is 32 bits and you are able to run “MAME.exe” by itself. If your system is Windows 64 bits, I have no idea otherwise why it isn’t working. (You DID install Direct X 9 from the folder called “- Fixes when not working!!!” Right?)