well i have problem with instaling.. i uninstall my net framework 4.then i download nfm 3.5. i try to instal it but at half of extracting its says:For instalation or setting up product ms .Net fm 3.5 you must use control panel turn on or off parts of system windows.So i go control panel and turn on or off part of system windows and then i find it. fm 3.5 SP1 i turn it on but with error and restart. after restart nothing hapend.its same. and now i think that i dont have any framework.i check it with some utility and that framework was instaled wrong.. what to do now?