13-01-2017, 04:33 PM
Ok, you fly in windowed mode only, but did you happen to update the graphics card driver? If you have changed absolutely nothing on your system and this window message appears, I would have no idea on why this would happen all of a sudden. Have you tried using FsP without the mini panel? Personally speaking, I used the mini panel years ago but quit using it. I either use hot keys on the fly or access the FsP menu in order to keep the screen uncluttered with other small windows. Certainly I know many others enjoy the mini panel and prefer using it, but sometimes multiple open windows can cause graphics issues and errors.
See FsPassengers Frequently Asked Questions: FAQ