Even with all overlays turned off it won't work.
Strange thing is that I can move a waypoint but not drag the map.

*edit*
I had to reboot after some windows updates and now it works fine again.

I suddenly lost the ability to drag the map with the left mousebutton.
I can zoom in and out with the scrollwheel and the map will center on the point where the mouse is when scrolling.
I can also make the map center on an airport or navaid with the find function.
I tried different mapsources and different setting for the mapsync with the useraircraft and FS connection.
FS is not running when this happens.

Any idea how I can solve this?