Recently, without any changes, the autopilot on the MD-11 deviates from the route to the right(as indicated by the ND), up to around 2nm. It cannot track a localizer either. I'm not sure what could have caused this, and I've tried reinstalling. Any ideas?I think it might be improperly correcting for wind

Hey,Could be a corrupted .rte file. Did you enter a pre-saved route into the FMC using the 'coroute' function ? On the PMDG 747, I experienced the same and on selecting manual heading mode, it would always take the longer turn in. Usually, it would turn left or right depending on which side is the turn radius going to be smaller but at times it would take the longer turn. Turned out that inputting waypoints as lat/long were causing it to go crazy. If its the wind, make sure that you have entered the exact 'winds aloft data', if you've entered anything at all. Try keeping the 'Central' autopilot in command for localizer tracking. Just suggestions that helped me from time to time. Cheers,Karan

I programmed the route manually. The MD-11 only has two APs, and I tried both.

Try the registry repair tool free from flight 1, run as admin if you have Vista/W7.If that doesn't do the trick, post a screenshot to help identify the problem.

I'll try the registry repair, what do you need a screenshot of? The ND?

Sounds exactly like they symptoms of a corrupted registry, the Fligh1 registry repair tool should clear it right up.