I tried windows XP,went right back to windows 98se ASAP.I have G2,no problems installing there,BUT,,,In my opinion whoever Great Planes contracted to write the program for them where really not up to snuff on game development.Look at the other current games out there,one word,OUTSTANDING!Where on the other hand take a look at G2,you have to upgrade the thing to get the add ons to work,lotta glitches,and the online play is a TOTAL JOKE!!!!!!!!!Lets just hope that the G3 version has some 'REAL PROGRAMING'and is quite a few steps above G2 which i think is the equivilant of the 'TOMB RAIDER'software for the PC,(JUNK!)I know i will not upgrade to G3 untill i get a chance to try it first.I purchased 2 complete G2 systems,$400,one for me and one for my son,,,,wasted money.For the price Great Planes charged for the G2 they should have done alot more homework on the software end and contracted a 'QUALIFIED'game developer before they released it to the public.