Gary beat me to it. Users rights account can easily be the problem,
especially, on a new system.
As he said, there are ways to get around it, but it'd be worth your time to just reinstall FSX in another directory.
People are probably sick of hearing me say this, but solid state drives are getting very cheap. You can get a
240GB for less than $60. For most people that will hold all of your FSX files for several years if used ONLY for FSX/P3d, and even the slowest SSD will be faster than your most hard drives.
That'll avoid the UAC problem, and speed up your flight sim in several ways.
BTW - the directory "
Program Files (x86)" is only a special directory on the C: drive.
If you use the same name :
Program Files (x86) on a different drive, not only will you gain the speed advantage of the SSD, you'll also find that simply using two drives, even if they are both regular hard drives, will speed up your flight sim.
And if you use the same folder name on the new drive, "
D:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\", then when you need to run install programs, all that you have to do is to change one letter - the C to a D.
PS - I just checked my 2-3 year old flight sim drive.
