The MAMEUI video game emulator for PC will commonly throw an error that says:
Error: required files are missing, the game cannot be run
This error can be caused by the game roms not being loaded properly, a misplaced EXE file, or video problems. To fix the issue, try the following.
1. Ensure game roms are in the proper folder. The EXE file that runs MAMEUI must be in the same location as the roms folder. Make sure you haven’t dragged the EXE to the desktop or another location, as it will not work properly without the folders in the proper place.
2. Make sure the video game roms are not corrupted and preserved in the ZIP format. Do not unzip the files.
3. If you are sure everything is in the proper spot, the problem could be caused by video issues. You can often fix it by selecting Options > Default Game Options > Advanced and ensuring that Switch resolutions to fit is unchecked.