If so, do you have the latest updates? Tell your windows 7 to look for updates and install everything. If you can not do that for some reason, delete DB and all of your .net systems, then run the installer so it will go looking for the latest versions. Over the last few weeks this has been a major issue. It took me a while to isolate it I kept thinking it had something to do with DB, but the problem really isn't within DB. When you try to look at what happened does it say "appcrash"? If so, it is very likely that this is your problem.