Today I was assigned an incident where the SharePoint administrators could not add permissions to a WSS site for a specific Active Directory user. The problem was the People Picker was not displaying any users – it just said “User not found” regardless of which substring I entered (and I ensured the substring was present in an existing Active Directory user’s name).

There are a couple of resources on the net for:

  • People Picker only shows a partial list of AD users
  • People Picker only shows a list of AD in specific OUs
  • People Picker has a bad day and just doesn’t like you today

But none applied to or solved my problem, my PP didn’t show any error, it just didn’t find any users.

One clue was that directly after the installation it actually worked and since then “nothing had changed”. Two existing users that were added after installation were still in the PeoplePicker cache, so I confirmed that it must have worked at some time in the past.

In Event Viewer I searched for errors during of shortly after my searched, but nothing obvious appeared. I then filtered for only “errors and warnings” and those that happened after the installation date and (apart from the classic DCOM permissions errors under a 2008 R2 installation) it showed me that about 6 days after installation the server started having NETLOGON errors along the lines of “Computer could not be authorized.” This continued until today. Turns out for some reason the computer account of the server in Active Directory got screwed up and after

  • detaching the server from the domain
  • manually deleting the computer account in Active Direcotry
  • and rejoining the server to the domain

everything worked again as usual.

HTH, Alex