Open GPS causing terrain.dll crash?

Just trying to fly a flight from Vancouver to Calgary for my VA and FS9 continues to crash on me with the dreaded terrrain.dll error. I checked out other threads with this error and then double checked to see if there are any duplicate AFCAD's and cleaned up any that I had and the crash still occurs if I have the default GPS open at a certain point in the flight.The crash occurs about 100nm west of Calgary. All of a sudden the screen will go black, the hard drive will come on and two minutes later, the error message pops up. I checked to see if anything addon scenery for that area could be causing the issue and even installed one addon, but the crash still happens.In another test, I was just sitting at Calgary (CYYC) and doing nothing, then opened the GPS and bang, right away got the exact same crash and error.So I overflew the first area where the crash was occuring and kept the GPS closed and no problem.Could having the GPS open and even just opening it from the start cause terrain.dll crashes?Many thanks for any and all replies.