Hi.After reading the recommendations from PMDG regarding problems with FSX and windows 7, I removed FSX from my C: drive and re-installed it on a second hard drive (F:). FSX Deluxe edition installed OK, and accepted the activation code, but after I re-installed the acceleration pack, whenever I start FSX, I gert a message saying "we're sorry, an unexpected error ocurred which is preventing product activation from being completed".Any reference to this problem that I've managed to find has been XP specific. Anyone any ideas?Thanks.Kevin O'Connell

I had the same issue and with this Microsoft fix i was able to active acceleration pack after reeboting.http://support.microsoft.com/kb/960480/en-ushttp://download.microsoft.com/download/1/7/3/173603C0-16DC-4119-80CF-ED711033CF31/MicrosoftFixit50176.msi

Also make sure you are not running the fsx.exe in any type of "compatibility mode". To check, right click the fsx.exe and select properties. Select the "Compatibility" tab. Make sure the "compatibility mode" box is unchecked.

I had the same issue and with this Microsoft fix i was able to active acceleration pack after reeboting.http://support.micro...kb/960480/en-ushttp://download.micr...tFixit50176.msi

Fabrizio, you're a hero! I'd never heard of microsoft Fixit. After hours of installing and re-installing, I had it working within 5 minutes of readiong your post. Thank you very much.

you can also edit the registry yourself to get to the activation screen.I learned it by watching the tech do it after installing a certain file from microsoft.She did it remotely in about 3 minutes.I've had this problem twice: the problem is solved at "upperfilters".I'ld tried that fixit tool but it didn't work for me.