I have run fsx for years on my win7 64bit os without any issues or problems. Same os, same hdd, same hardware and when I go to activate...error. After spending 2 hours and being transferred to 5 different extensions, Microsoft will not activate the product because of compatibility issues. When explained that it had been activated previously on this os, I got the telephone equivalent of the 10000 yard stare. Acceleration, is compatible but not FSX Deluxe. When I explained that I purchased the 'Gold' edition of the product which came as Deluxe with the separate Acceleration disk and that to install Acceleration it requires that FSX Deluxe copy to be validated. Still the 1000 yard stare. Has anyone else experienced this inflexibility on MS's part? BTW. if anyone else has fsx installed on a 64bit system, Microsoft just wants you to know it doesn't wotk.Jon

Are you missing the CD key? I lost mine once, and I called MS and read them the serial number off of the disc (it's on the clear center ring of the disc) and they were able to generate the key for me. Never had any issues after that, and I run it with Windows 7 64, but I didn't tell them anything about what OS I was using.

Call the number and just keep pressing zero when the automated machine asks you to punch in the keySomeone helped me and reset the activation amount for fsx

I have the professional edition and everything with the activation worked like a charm.

Same here. FSX Deluxe activated no problem on my W7 64bit system. Compatibility never came up on install.Bob

Have you made sure you installed it as an admin etc etc. There is a way to modify the exe properties to suit the OS. I.e changing the compatibility.But it definitely works on win 7 64bit as that's the OS I use too.Tom

Jeez...and then companies wonder why piracy is spreading...Sorry I can't be of more help.