hi, i'm sure this is on here somewhere but i've now confused myself. I'm not sure what happened. I keep my computer (dell inspirion 1521) in sleep mode. got home from work, opened it up and it started weirding out and rebooted itself.problem is now it wont go past the startup. it tells me to insert the windows disk to recover, but when i do, it's like it's not reading it. I keep getting the same 2 screens over and over. I did finally get the the advanced boot options but there is no "repair" options so now i'm lost. it's telling me file: windows\system32\ntkrnlpa.exe status : 0xc0000428 info; windows cannot verify the digital signature for this file. when i was in the advanced mode, i tried to bypass the signatures but it brings me right back to this screen no matter what i do. (grrrrr) any assistance would be greatly appreciated.