There is a last-ditch stopgap measure to help - you can delete your preferences, then X-Plane will make new ones when you launch it next. Note that this is at your own risk!
Navigate to
X-Plane 10\Output\preferences
Rename your X-Plane.prf to something else, like X-Plane.bak (for example).
Then try to start X-Plane again.
Good luck, Jan