I have recently installed the winter schedule for Continental airlines and now I get 2 aircraft sitting one on top of each other at various gates. I have tried to use AITM for duplicate flights but don't know how to fix the problem.Why is this happening and how can I correct it?

It sounds like you have 2 parking spots for the same gate. Have you added parking spots using AFCAD? Or downloaded an AFCAD file for that airport? Go into AFCAD & move the parking spot where you're getting 2 planes. You'll most likely see a 2nd spot underneath that one.John

...or you've got 2 overlays for that airport, each with a spot at the same gate. It's a little tougher to find the duplicates in this case, but if you know which gates are causing problems you can just put a plane there, bring up TWO copies of AFCAD and put one overlay in each. If you have FSUIPC, then you will see the aircraft position marked on each of the overlays and you can decide which parking spot to delete.

Another possibility - static aircraft in sceneries. The recent Halifax scenery has some statics, as do a few others (KISP as I recall was one.) You need an AFCAD file which does not have parking at those gates. In the case of Halifax, you can simply remove the .bgl files for the aircraft and they will not appear. (This was my solution, because Halifax doesn't have a large number of gates, and even my modest AI was filling them.)