Hi I have this problem too. But only when I use add-on sceneries as start up location it seems. (UTX Europe, FTX Coffs harbour etc. )If I use a standard FSX scenery as the first start up location the FMS will power up, also when I switch to a add-on scenery.I load the default trike first, then I switch to JS41. Is it a known problem that add-on scenery can make trouble for the FMS?OS: Win XP Pro with the latest updates.Regards