Major Crash

I have downloaded 2.57b 64 bit and installed. When I try to open, I get message Blender Has Stopped Working. I am using Win 7 64 bit. Had previously be using 2.57a 64 bit successfully then just yesterday started getting the same message. 2.49 works fine. Have tried reinstalling, cleaning registry, etc. Any suggestions? (I’m not an expert in PCs). Thanks. Dale

well it looks as though your computer still has some old files from your other version on there, which is causing problems in your download…check your application directory (c drive, applications, blender foundtaion) and delete everything in that folder, then uninstall, then clean your registry, and then use CCLEANER, (its free) to wipe your recent stuff, and then download 2.57 as well, because I had this same problem, and thats what I had to do