Incompatable aircraft or software

I have several old third party airplanes that I have been flying for a long time. Now that I have downloaded these airplanes into a new XP computerFS9these airplane will messed up outside appearance. Message reads"Flight simulator has detected potentially incompatable aircraft or software EXP1(c182\model\cessna1825_n.MDL) or it could be a gauge error message such as File gauges\B767Apilot.gau. These airplanes are now listed as Unspecified in the menu. Something seems to be wrong with the model forms on the outside. Everything is ok inside cockpit. Can you help me?