On an internal network, we use ntp between our servers but they slowly get out of sync with the real time. Most users are running Windows 7, and the domain is on Windows 2008 R2. We have an Ubuntu 9.04 server with some shared folders running samba 3.3.2. When we changed the time to reflect the real time, most users had issues accessing this share. Once they rebooted most were fine. The ones that still had issues, I did some googling and found a command: net time /domain:domain.com /set. That fixed most of the users left. There's still one user left being unable to access the shared folder (possibly others). The exact error message is: This server's clock is not synchronized with the primary domain controller 's clock. I had a look, he has the proper timezone, time is correct, daylight savings time setting is correct. Not sure why else this is failing. Ideas?