repairing unbootable pc


I have a friend whose vista pc will not boot after installing system updates. She does not duel- boot, only runs Vista home. I have tried repairing the problem with the vista dvd, it cannot repair the boot problem automatically. It does not detect the operating system. I am wondering if I can fix it with easybcd by using my vista machine. Any advice is appreciated. I have never used easybcd and want to make sure it doesnt screw up my pc. Thanks.
have you run a system repair with the original system dics at all @ jdawest?? that should repair any problems!

hope that helps.
You wont be able to use your machine. Even if you could fix the boot problem, the boot process would not continue due to the fact that the hardware profiles of the machines do not match and using her drive you would get a whole new set of problems. There will be no way to do it from your machine.

You say that the disk doesnt detect the OS. Does this happen every time you try to use the disk or did you try only once? You may have to backup her files using a Linux LiveCD like Ubuntu and reset the system to factory settings.
Two things to check.
First, are there multiple HDDs ? If so disconnect the others while you try the repair.
Second, does the Vista partition have the "active" flag set ? If not, set it active before trying the repair.
never could fix it. The bcd was missing, I kept rebuilding it using the vista disk, it kept disappearing after every reboot. I finally gave the pc back to the owner and referred them to a professional repair shop.
Thank you all for the suggestions.