If CyberStalkers advise doesn't work, then I might add that I had similar problems with Sonic that came preinstalled on my PC. Not the kind that you are having but something to do with burning audio or videofiles. It burned allright but I wasn't able to play it in any cd or dvd player. I took the easy way out and deleted Sonic from my system and installed better software

I have no idea how the paid for version works, because the free version pissed me of too much