If Nothing Works Then Follow this
Try Startup Repair from the Recovery Console (if you have one) or from a Vista disk - if you do not have a
Vista disk you can borrow a friends (they are not copy protected) or make one. Also your System maker will
sell the physical disks cheap since you already own Windows.
This tells you how to access the System Recovery Options and/or with a Vista Disk
http://windowshelp.microsoft.com/Windows/en-US/Help/326b756b-1601-435e-99d0-1585439470351033.mspx
Try StartUp Repair from Recovery Options and/or a Vista disk.
How to do a Startup Repair
http://www.vistax64.com/tutorials/91467-startup-repair.html
Also from the COMMAND PROMPT of Recovery Console (if possible) or a Vista disk
SFC /scannow
Hit Enter
and after that runs
chkdsk /f /r
Hit Enter
( Spaces between C and / k and / and f and / )
Retry Startup Repair after Chkdsk.
If needed after those you retry System Restore from the Recovery or Vista disk.
How to Do a System Restore in Vista
http://www.vistax64.com/tutorials/76905-system-restore-how.html
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If you need to make repair disks - these help repair Windows not re-install.
How to Make a Bootable Disk in Vista
http://www.brighthub.com/computing/windows-platform/articles/7050.aspx
Download: Windows Vista x64 Recovery Disc
http://neosmart.net/blog/2008/download-windows-vista-x64-recovery-disc/
Download: Windows Vista x64 Recovery Disc
http://neosmart.net/blog/2008/download-windows-vista-x64-recovery-disc/
How to Make a Windows Vista Repair Disk If You Don’t Have One
http://www.howtogeek.com/howto/windows-vista/how-to-make-a-windows-vista-repair-disk-if-you-dont-have-one/
Hope this helps.