The Machine SID Duplication Myth

[Jonathan de Boyne Pollard]

BUT, what concerns me is you stated these machines are imaged. Did you use Sysprep, or are these machines mirror copies of a base image?

If mirrored copies, I can see what's going on - it has a duplicate SID.

I've have good luck with NewSid.exe It even works with with Vista without fouling up the activation if it was activated before the image was made. It's freeware.

... and Mark Russinovich explains that a lot of the thinking that underpins people's desire to run it in the first place appears to be ill-founded, with duplicate SIDs not actually being the problem they are often thought to be.  Hence the tool being retired last year.