Hi Dan,
Many thanks for taking care of my issue. I already signed PF3 to start as ADMINISTRATOR.
But it was always started while AIVLASOFT was also started. I will try this out and will start PF3 after the flight plan was created and saved properly.
I will report my outcome.
Cheers
Pascal
That's NOT what Dan suggested. Please read his post again
In your main PF3 folder, right-click on PF3_Register.exe and select 'Run as Administrator'. Wait about 15 seconds or so and then start PF3 and try loading a flight plan.