Hi my computer was working fine last night, but then when I tried to boot it this morning I got: Windows could not start because the following file is missing or corrupt windows system32 config system. Safe mode doesn't work, last known good configuration doesn't work, and I tried to do a repair install but it didn't seem to see my previous installation of windows. I haven't made any changes to anything AFAIK. I read this but it seems that you need to use safe mode. http://support.microsoft.com/kb/307545 Thanks for your help.