Can't get Vista SP1 to install

Here's my situation. I bought a custom gaming PC about a year ago and it came with Vista Home Premium 32bit. Since SP1 was released, I've tried several times to install it both through Windows Update and manually but it always fails. I looked at the information in the Knowledgebase article about the error message I was getting and it suggested running a system scan utility through the command line interface which I did. The utility said that it fixed some files but I had corrupted files that it was not able to repair.

I went out and bought an upgrade version of Vista Home Premium that contained SP1 thinking I could just upgrade it as a workaround. No dice, the upgrade option is disabled unless you already have SP1 installed. It will only let me do a clean install. This brings me to my first question. If I do the clean install, it's going to format my HD right? I'll have to reinstall all my software?

My second question is, does anybody know how I can get SP1 to install on my current installation? Any way to find and repair those supposedly corrupt files?

Thanks in advance

I've been battling with this all night and the better part of this morning. I think my best bet is just to do a clean install of the OS.

Can you guys please let me know what I should backup? I won't lose my software but the registry entries will be gone correct? So I'll have to reinstall that stuff anyway?

Hello Peter,
I don't know how much it will help you, as I don't have SP1. Here is a link showing you several resoluions.Good luck.

Error message when you try to install Windows Vista Service Pack 1: "Installation was not successful" or "An internal error occurred while installing the service pack"

I already tried all that but thanks for trying.

All I really want to know now is what I'm going to lose if I do a clean Vista install and what I need to backup. I haven't had to do a clean install of an OS to fix a problem since I was running Windows 98.

I seem to recall that, back then, it would not format the HD and delete everything but your stuff like My Documents and what not would be erased. All the software you installed would still be there but all the registry entries go poof so it needs to be reinstalled.

That's what I'm wondering about now. If anybody can confirm or deny those things, I'll get started on doing this reinstall.

Hello Peter,
If I were you, I would save files/folders that I wanted to keep on cds before reinstalling. I have never done a clean installing, but I do know you need to re-install all your drivers. You should have a DRIVERS & UTILITIES disk that came with the computer. (Mine did.) That's just about all I know. Good luck.

What is/are the error message(s)?

You mean when I run the file scanner?

So what is the error message ?

Service Pack failed to Install error 0x800F0826

So, open Windows Update, in the left pane, click View update history and check the updates that have failed to install.
If any updates failed, please give the error details.
On of the reason of this error is that one of the prerequisite update pre-SP1 failed to install.