Windows Vista Cant boot up

Hi, I need with my pc.

It's a custom built pc with vista ultim 64bit.

Yesterday I installed adobe illustrator cs5. And now my pc wont boot after a restart. The only thing on my screen is a blinking underscore. I can't even get into safe mode. It loads the monitor logo and it goes straight to the blinking underscore.

I do have vista cd (system builder). I tired to use the cd to repair it. But when I went to startup repair, it shows nothing to repair. When I hit load driver, it shows all my hard drive and files. I don't know what to do there.

Went into system restore. It shows up a message about offline system restore.

In complete pc restore, it has no backup files.

What can I do?

 

Ok I update my system. From the MBR link you post, the only option that work was /fixmbr. It was successfully complete. Now I restart the pc and I end up back at the beginning. Blinking underscore....

I tried /fixboot, but it said unknown element...

 

Try this if chkdsk does not improve things.

Boot from the Vista disc and run the Upgrade option, this will repair your file system.

If that does not work then I would suspect that your hard drive is faulty. Download the DOS CD version of the hard drive diagnostics for whichever drive you have your OS installed on, burn the image file to a CD and reboot with the CD inserted. Run the diagnostics on the OS drive.

Seagate, Maxtor & Quantum:http://www.seagate.com/www/en-us/support/downloads

Western Digital:http://support.wdc.com/product/download.asp?lang=en