Hi Fang, Having been a proxy user for years, i too sudenly developed this curious problem and it also had me jumping through hoops (I'd much rather be flying though them!!). I was stumped and tried everything until i found a solution thats worked for me and i thought this might help you too. Basically i thought about what i had changed since the problem started occuring and i realised i had installed the VFR real scenery collection from Just Flight (awesome addon btw). So i went into the scenery manager and disabled the VFR real stuff and low and behold my TP problem was resolved. Bit of a pain to enable/disable the scenery when i want to use it but hey what ever gets the boat afloat right :( .I have to point out that before i done this i had uninstaled FSX SP2, repaired FSX then reinstalled SP2 so maybe try that if the first option fails or indeed you have no other scenery installed.Anyways, hope that helpscheersSteve