Thank you for the response, as I mentioned, I found a post on this forum which stated that full ROM sets can be downloaded from a link in the post. I downloaded the exact file listed as a full ROM set Merged. Also, when I try to import roms, there is no folder option for MAME or Arcade to put the ROMS in, the only options are a list of game consoles, Windows, and Android. Since they are Arcade games I don't think I should place the ROMS into Atari Jaguar for example.
Also, I have tried several Full MAME sets from other sources, but get the same message.
As I mentioned also, I am running Windows 11 and wonder if this is the issue. The actual gaming PC wil run windows 10 Pro 64 Bit. I;m just setting up the gaming drive with my laptop, while I wait for my new processor.
Thank you for your help