[DaveBurnett]

I have MSDN so can and do use my Vista more than once on the same disk.
I use a third party boot manager that dynamically changes the partition table so that each installation thinks it is the only one.

Now my problem is that when Vista does an automatic update on one of my versions, it registers it as having been applied (at the Microsoft Site) and refuses to apply it to the other version when I boot into that.

Does anyone know a way of forcing it?

[JohnWill]

Hmm...

You might try posting in the MVP Newsgroups, I'm not sure how you'd fool it into working. I've installed my MSDN XP on several systems, and even a couple of copies in Virtual Machines with no issues, but not Vista.

[DaveBurnett]

Solved it myself - actually it wasn't a problem when I compared the items themselves and ignored the dates - which are the installed date NOT the patch date