I just did a flight with the Just Flight 757-300,and although the flight went well, I had some problems initially. The first problem was that IYP wanted to download the airport data when I launched the flight with this aircraft. I was parked at a gate at KIAH. IYP then told me that no flight plan had been loaded, which was incorrect. So, I went back and reloaded the same flight as I was just starting, and the same thing occurred all over again. I then had problems requesting IFR Clearence, Taxi, and Take off clearance. After getting off the ground things went well until landing. Jordan