Ran into a bit of stupid today--I doubt the details matter too much but I was attempting to install the Hyper-V MSU and the Hyper-V role in Windows Server 2008 when I came up against this message in both cases:
No mapping between account names and security ids was done
Naturally I told Windows I don't care and to sort itself out but it wouldn't listen.
I finally realised I'd renamed the Administrator account as I normally do but hadn't logged off or rebooted. I rebooted just to be safe and that fixed the problem.
Custom-Built Microsoft Office SharePoint Server 2007 Branded Sites and Webpart Development - firstname.lastname@example.org