FPS drops to almost zero when using FMC in flight

[SierraHotel]

FPS drops to almost zero when using FMC in flight and stays there! However if I pre-program the FMC with SID and STAR and don't touch it I can complete a flight. Not so great if you are flying online.

[donoscar]

had the same issue till i discovered windows defender had re-activated itself after windows upgrade. try to see if your anti-virus is the one to blame.