I upgraded to Win 10 last night, tried to run faf today and no go.
The logfile 'C:\Program Files (x86)\Forged Alliance Forever\FAForever.exe.log' could not be opened:
[Errno13\ Permission denied: 'C:\\program Files(x86)\\Forged Alliance Forever\\FAForever.exe.log'
I uninstalled it, reinstalled it. I found that all the files and subfolders were read only so I changed those permissions (had to reboot for that to work properly >.<) and it still not working. I created a file called FAForever.exe.log using the DOS copy con command and that worked but its still no working (file is NOT read only). I have tried reinstalling it 3 times now and its still a non starter.