I had the some problem today,
my solution was changing the language back to english in the windows control center.
i tried to install the vCenter on a english Win2008 R2 with german language pack and switches to German.
Switch to english und retry was the solution.
Please check out installation logs for Update Manager.
You can find useful information here.
My Vmware blog: http://geeksilverblog.com
I just had the same error while upgrading to Vcenter 4.1(lucky I took a snapshot). The machine is a windows 2008 R2 localised Italian with English language. I was hoping not to install a new w2k8 R2 server in English and move the database with View Composer (it's on the same machine). Is there any other solution to the problem? Possibly a workaround?
Thanks for any feedback.
I had the same problem.
Reason: Windows Server language was Russian, vCenter - English.
Solvation: Change the OS language to English.
P.S. As far as I know the same thing with German.
Remove the installation media. Do not use the add and remove windows programs.