I have installed FSX previously with a successful online validation. To open the sim being a simple click on the FSX.exe to fly. My OS is Windows 7 64bit and the sim has it's own HD (D:\FSX).I decided to do a fresh install of the sim so followed the recommended steps, removed any addons such as aircraft, scenery and weather. Then uninstalled FSX SP2 followed FSX itself via Control Panel. Deleted any FSX files located in AppData under Microsoft etc. So my system was clean ready for a fresh install of FSX.Went through the normal process to install with disc 1 and 2 then actioned the online validation loading it up to the point where the main interface screen appears, closed down sim. Next installed SP1 and SP2 running the sim after each service pack.To my knowledge there has only ever been the need to run the online validation once following the initial installation, the sim would always open with a simple click of the FSX.exe.The problem I have now is the need to enter the key for online validation each time I select (click) the FSX.exe to open the sim. Is this something new that MS has introduced or would it suggest my OS has a problem within the Installshield folder causing errors during the installation of FSX.Would a fresh install of Win7 resolve the problem?Any advice would be appreciated.Derek (Delf) Froud

Might want to try the appropriate PMDG support forum here.Cheers,- jahman.

Edited February 4, 201214 yr by jahman

Just a guess, but perhaps FSX doesn't have permissions to write the config/registry file that stores your registration info. Make sure that your AppData and FSX folders are not read-only.

Thanks guys but I have fixed the problem, simply overlooked the need to select Run as Administrator for FSX.exe then the validation is automatically recognised.Cheers