Hi Roberto,
The Microsoft Windows 8 Compatibility Center website appears that Microsoft Flight Simulator X: Acceleration is compatible with both Windows 8 and 8.1.
You could just google Microsoft Flight Simulator X and download, but please note:
Do not install it to the default path, which is C:\Program Files (x86) etc. If you do that you can be certain you'll have problems with addons because of UAC in interfering. Instead, install to something like C:\FSX, or to a different hard drive than C:
if you have one.
Second, don't run it off the tile screen, but run it off the desktop.
And third, run it as Administrator.
Regards
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