I have a corrupt boot critical file c:\ntoskrnl.exe which prevents me from downloading new
programs and updates. Ater the initial setup, I need to restart the PC for the downloads
to take effect. Once I do this, the computer takes forever to shut down while it's "configuring
updates", then again after it starts up. THEN it reads windows could not restart, and THEN the
windows automatic repair starts, taking another 20 min., THEN AFTER ALL THIS - any downloads,
new program installations, updates, etc. are COMPLETELY GONE!!! So I was hoping to restore
to an earlier date but the earliest restore point is only a few days ago. I never got an installation
disk when I bought my computer (My OS is Vista 6.0) So I'm pretty desperate at the moment. I hope someone
help me out with this - PLEASE!

Boot into safe mode and select " last known good configuration" option

Start into SAFE MODE

1/As your computer starts but before Windows launches, press F8 repeatedly.
2/Use the arrow keys to highlight Safe Mode, and then press ENTER.
3/If you have a dual-boot or multiple-boot system, choose the installation that you need to access using the arrow keys, and then press ENTER.
Note: If Windows launches before you can choose a safe mode, restart your computer and try again
PS/ Sometimes it maybe the F5 key