So here is the scenario. I'm uninstalling vCenter, but leaving SSO because I am testing something. I go to upgrade SSO 5.5 to 6.0, I get an error of "Cannot start vCenter Service" or something close to that effect. Uh ok, why? vCenter Service isn't even there, Turns out, my uninstallation of vCenter did not uninstall VCSServiceManager service properly and it now is stuck there.
- Visit this page from the affected system
- Make sure to add http://*.microsoft.com and https://*.microsoft.com to your trusted sites list in IE.
- If you don't, well, you'll likely end up in IE hell.
- Run FixIT and run through the wizard to have it remove the VCSServiceManager install.
The vCenter installation for 6.0, I guess, detects this VCSServiceManager and bombs on the upgrade even if it is just SSO. So I'd run the uninstall manually and the entry wouldn't go away. No interactive error, nothing. Looking at event logs would show that the uninstall bombed w/ a MSI error of 1603. Basically you have to debug it from what I read.
Then I was dealing w/ wonderful IE security while trying to run the above Microsoft FIXit app. Once I got around that, it was able to successfully cleanup the stale/broken entry and SSO 5.5 to PSC 6.0 upgrade worked perfectly.