skeps1s

I can't repair Vista. All of my games got low performance at one point (no matter what settings I run them on). I did everything I could: defrag, system restore, etc, but nothing worked. So I tried downloading the newest Direct X End User Run Time. When I started it up it told me my files were corrupt and it couldn't install. I haven't done a Vista reinstall in about two years anyways so I decided to do it.

Problem is I can't figure out how...My PC had XP to start with, but I bought a Vista "upgrade only" CD before SP1 for Vista even came out. If I boot from the upgrade disc and get to the repair part it says it can't recognize if I have a Microsoft OS installed. If I launch the Vista CD from my desktop it does an install of Vista (without asking if I want to repair or anything, it just goes straight to installing as soon as I choose the language), but half way through, it tells me I'm missing files or my files are corrupt and it aborts the install.

I can't wipe my Hard Drive because I lost my original XP CD (I still have the CD key) and the Vista Upgrade Only CD won't work unless I have an OS. installed already.

Please Help. I am very good with PCs so if you have any questions that need answers then please ask, I can probably answer it.