Last night I installed norton antivirus on my moms computer and the install went smooth, but before I left I started a full system scan and this morning when I went back all I seen was a black screen, so I tried to reboot it and it would not work! I get something that comes up saying <windows root> \ system 32\ntoskrnl.exe file missing or corrupt...what happend? Did norton find a virus on a system file and delete it? Is there anyway to replace this file, I cant even boot into safe mode and I have tried to boot into the option of (last known good configuration) and I get the same message! She does not have a system restore disk what else are my options? Someone please help!