That happened to me too and I had just installed master collection on fresh drive. Only way I was able to get around it was (ok, this sounds stupid but) to make a new account. The new account has all the same rights as the other the only difference is the program works fine on new account. That fix was actually all the help an adobe tech was able to come up with. Before I sent my tower to the builder to be looked at for other problems I was running CS3 Production Premium and I didn’t have that problem. Got the computer back installed Master Collection and the program would crash like you said.