When I tried to upgrade my vCenter 5.0U1 Server to 5.1, all seemed to go well, up until the the moment vCenter tried to register with SSO.

I received an error message “Error 29107. The service or solution user is already registered. Check Vm_ssoreg.log in system temporary folder for details”

I checked this log, but it did not really point me in to the right direction.

Then I found a post in the 5.1 beta archive that said the unique identifier for a service to register with SSO is the Common Name from its certificate. Continue reading →