Recently trying to use Windows Update at a customers site that has SBS 2003 Premium R2 (with ISA) and received the following Windows Update error 0x800A0007 on every machine. Hmmm...this wasn't happening last time, what's changed? Did some searching on the Net and found a multitude of solutions from simple clearing of the IE cache to reformatting. The common point seemed that this issue was caused by Microsoft Genuine Advantage (yuk!).
So we went to the Microsoft download site and installed Windows Genuine Advantage on the machines manually. The secret is then to reboot the machines and try Windows Update again. Worked on all the machines.
Nice isn't it that a piece of software designed to ensure you have a legal copy of Windows stuffs up keeping the software up to date? Gotta admit with all the problems that we have had of late we are no fans of Windows Genuine Advantage. We think that perhaps Microsoft should test this sorta thing more thoroughly, but hey that's just us.