Star Wars: Empire At War running with image

[cptpooface]

I just mounted the image with DT and ran SecuRom using the sweaw in game data. That worked for me twice then I started getting the "original disc could not be found or authenticated" message. I didn't patch the game or anything, it worked earlier today but tonight it just stopped working. I searched the forums and this seemed to happen to a lot of people. Any ideas on why this happens? I don't think it could be the image because it wouldn't have worked at all if it was a bad image. I tried it ten times and figured if it was going to work it would work one of those times, but it didn't. Can the program somehow get "smarter" and figure out there is no disc? I guess I'm back to using the original disc until someone figures this out.