YES! This was the solution!
I tried the Google Maps mod, and it didn’t work as I dreamed, so I uninstalled. I missed the read me -file’s sentence:
“To restore the previous state, please delete
The following two lines in the C:\Windows\System32\drivers\etc\hosts file:
```
127.0.0.1 kh.ssl.ak.tiles.virtualearth.net
127.0.0.1 khstorelive.azureedge.net”
That was the reason. I deleted those two lines from my System32 and the Flight Sim works once again like a charm!
Thank you Goodman98155!