Whenever I try to boot my computer the "welcome" message on the start up does not appear. The graphics appear to be changed a little, but can successfully login to my account . The desktop icons are displayed without the corresponding descriptive text for example I can see computer icon but not the "My computer" tag same with all icons. Right clicking on anything pops up a menu without text just a white box. Clicking activity never works and the system just crashes with a blue screen or a blank screen in few seconds.The issue started after I ran sfc/scanow command through command promt. I got several errors in system files which it fixed but not for the good(apparently the tool suppose to help users got me in trouble). Subsequent attempts yielded no errors. safe mode just displays windows icon , nothing else.Some history: I have previously used several theme softwares which tweak the system files but uninstalled it later. I tried to repair the installation using the DVD but it couldn't find any problems. Also the DVD is without servive pack 1 and I have Windows 7 SP1. couldn't uninstall SP1 through command line it just pops a blank white screenPlease some one help me out I have lots of engineering software tools I use for my college work so cannot afford a disk clean up as I don't have installation dvd's and cannot afford another student's licence.