Kerberos Error

Of all the things, unexpected authentication errors from Kerberos are my least favorite. Mostly because, once I get the authentication set up, it's one of the things I expect to change the least.

I got the following error while trying to log in to the my lab:

Cannot connect to SQL Server.

The target principal name is incorrect. Cannot generate SSPI context.

Turns out, it was cached settings to blame, and running the following commands flushed the old settings and allowed a successful connection.

• klist purge
• ipconfig /flushdns

Joining a domain

When I wrote the how-to a few months ago, I forgot to jot down how to join the domain in both Windows 10 and from the command line.

To join an existing domain from Windows 10:

Right click on the Start button
Choose System from the pop up menu
Choose Advanced System Settings from the menu on the left
Choose the Computer Name tab
Click Change
Click Domain, and follow the prompts to enter your username and password


From the command line, for example, from a new test VM:

Open an elevated command prompt, and then type
netdom join machinenamegoeshere /domain:domainnamegoeshere