Vista and SBS2003 (in)compatability

One (new) client has unfortunately a Vista desktop purchased a couple of days before we took over IT and it needed joining to the domain. This has proved a difficult task to say the least. Our remote control software stops showing the users screen whenever the UAC prompt pops up (and freezes our screen until the local user clicks ok) which means the end user has to remain at their desk when we are doing any troubleshooting rather than letting them use another computer to do some work.
Anyway, the server/connectcomputer wizard was complaining that I needed admin rights (which I had already) and a patch is available, KB926505 but when I try to install that on the server I get the very wonderful error message “Failed to install” with no details as to why. Nothing in the eventlogs either. Add/Remove Programs now says the patch is installed and when you try to remove it, I get a message about all sorts of programs failing to work and the end of the world so I’ve left it in place until I get a chance to remove and reinstall the server whilst I am on site as opposed to RWW’ing into the server. In the meantime I joined the computer to the domain manually, and I’ve had to change the logon script so it doesn’t UAC whenever the script does the sbs setup program. Apparently this is fixed with the patch, so the patch obviously doesn’t work – watch this space.