Kerberos Configuration Manager for SQL Server error "unable to access user principal information from the system"

I know this is a really old post, but for anyone that is still having this issue... I managed to work around it by going into my local administrators group on the server and clearing out any accounts showing up as a GUID.

Once I did that, I was able to launch the tool, fill in no server/user info and just hit connect. It logged right in after that.

(I know the original poster said he already checked for that, but this is what resolved this issue for me).

I know this thread is old, but I was having the same issue. In my case the Remote Registry service was not running. I have found that on some servers it is just running, and on others it shows Automatic (trigger start), and in both of those cases I can use the tool successfully. If the service is manual/disabled, etc... and not running, this error occurred.

Mine was similar to the other answers but slightly different. I had an account from another domain in the Local Administrators group. I'm not sure the exact type of trust that was present. After removing that account the tool was able to run.