hi, my name is alex and im new,i have a problem with my 757 add on,why does only my left fuel tank burns?and when it comes to zero the planes engines stop working?sorry for my english im italian but lived in boston for 15 years but i dont remember some words.thanks

Make sure that the fuel tank selector on your default aircraft (the aircraft that appears on the FSX Start Screen when you first start FSX) is cet to ALL. This is one reason why the C172 is a good choice for the default aircraft in FSX and switching from it to the more advanced addon.

If you want, you could (maybe should) get the Safe Startup flight for Complex Aircraft from Flight 1: http://www.flight1software.com/files/FSXSafeStartup.exe

Note: You can re-save the flight in a new location, with different weather and start up times, but do not change anything else when saving this flight.
Important! You MUST start FSX with this flight for it to be effective. If you start FSX with another flight, load this one, then go to your complex aircraft, you may get undesirable results.

thanks a lot,ill try and let you know

thanks man,it worked your a real genius,i have just one more question,how come the plane crashed when i touch the ground i was at 135 speed and had 33% of fuel stiil on board,i disengage the autopilot at about 600 feet;was i too fast??? :-?

No worries. Glad I could help.

As for why you crashed. I just don't know enough about the circumstances to be able to say why. I don't know if 135 knots was too fast/too slow because the VAPP is base on the Gross Weight at the time of landing. I usually get that info from the APPROACH page on the CDU. I also do a full Autoland most of the time, so it doesn't crash when I land. But if I do do a manual landing, I usually turn the Autopilot and Autothrottle OFF at about 300-200 feet AGL, so I don't have much time to mess it up before I have landed.

ok,ill try an do an aotoland and see what happens,thanks a lot for your help ;D ;D ;)