Backup script and UAC conflict

I'm trying to use a backup batch file in Vista that I used for years with XP.
I don't really want to get into Vista's built-in backup, I'm just looking for
a solution for my batch file.

First off I'm using Vista Home Premium which came on the PC and can't afford
right now to upgrade. I'm using it in a 2003 domain at home which I built
years ago. Obviously VHP can't join the domain which is where the problem
starts.

I tried running the batch file but it wouldn't get far. I started
troubleshooting it and found the problem. The batch file utilizes some dummy
text files which are stored in C:\Windows. Anyone who has used Vista for
awhile knows that Vista's UAC doesn't like users, even those with "admin"
rights, messing with files in there. So I was getting access denied. I run
TweakUAC to run UAC in Quiet Mode as I really don't want, or have a need, to
turn UAC off.

But I found out that this is exactly what I have to do. If I turn off UAC,
then the backup batch file runs just fine.

Are there any commands I can add into my batch file to bypass UAC? Or is
there any other way to run the batch file and have it manipulate the dummy
text files in C:\Windows with UAC turned on?

BTW, I tried running the backup batch file from an elevated command prompt
and that didn't work either since then it couldn't authenticate to the server
where the batch file backs up the data to.