Dual Boot Problem

I had Windows 7 and Vista installed on seperate partitions for the last month or so. This morning I decided to (legitimately) upgrade Vista to Ultimate x64. All went well, but, now, BIOS or whatever doesn't recognise my Windows 7 install when I turn on my computer. It just isn't there. And, in system configuration through Vista, it says that Vista is the only OS. The partition containing 7 is still there and isn't any different from before I upgraded Vista.

Any ideas? Thanks.

Edit: I think it's possible that the Vista install changed the drive letter of the Windows 7 partition. I can't remember what it was before - any way of finding out? Or is it just going to be a case of trial and error?

Capt'n Midnight

Microsoft installs only recognise previous microsoft versions.
Installing windows all remove option to boot into Linux or newer versions of windows

you should be able to do a repair using the windows 7 dvd , cba looking it up

I can't see any repair option. If I was to reinstall 7 would it fix it? It wouldn't go not recognising Vista then, would it?

Thanks.

c-note

i have zero experience with vista or windows 7, but i know with xp if you have "n" partitions with "n" installations of xp, then one partition (whichever is installed first) contains the "master boot record, MBR" which is a little file which says what OS's are installed and on which partitions,

just a thought but could you inadvertantly overwritten the MBR when installing the new vista version?, in which case you need to fix the MBR (tell it that w.7 is installed on the other partition)

to get to the MBR on xp right click my computer>advanced tab>startup and recovery>edit startup file manually.
may be something similar on vista?
just a thought!

Thanks guys, got it sorted. You were right about the repair option Captain.