The session setup from the computer %computername% failed to authenticate.

I've been seeing this error come through on my Domain Controller System Event logs for some time now and finally figured out what the cause is. The Error is System Even ID: 5805

Event Type: Error
Event Source: NETLOGON
Event Category: None
Event ID: 5805
Date: 3/30/2008
Time: 10:16:24 PM
User: N/A
Computer: DC1
Description:
The session setup from the computer %computername% failed to authenticate.
The following error occurred:
Access is denied.

My Computers that are connecting to the Domain are Lab Computers for Student Computer Labs. We use a product called Deepfreeze with restores the computers to the last frozen state on every reboot. The one problem with using DeepFreeze and having the computers on the domain is that when the computers try to to a domain machine account password change they will forget the new password after a reboot. Now the computer won't login to the domain or setup a session. I fixed this by adding a group policy to all the Frozen Lab Computers that disables machine account password changes:

It's under Computer Configuration -> Windows Settings -> Security Settings -> Local Policies/Security Options -> Domain Member: Domain Member: Disableachine account password changes

There are multiple accounts with name cifs/102-PC12.domain.edu of type DS_SERVICE_PRINCIPAL_NAME

I've been having the following error logging on my domain controllers about every hour for quite some time now and finally got around to drilling down to figure it out.

Type: Error
Event: 11
Date Time: 8/29/2007 7:46:33 AM
Source: KDC
ComputerName: DC2
Category: None
User: N/A
Description: There are multiple accounts with name cifs/102-PC12.domain.edu of type DS_SERVICE_PRINCIPAL_NAME.

After a little research and lots of luck... I decided to use ldp.exe to do a quick search of the (serivceprincipal=*.102-PC12.domain.edu). What do you know... it came up with 2 accounts sharing that name. I quickly found the one that was a problem and deleted it. It turns out somebody put an image on a few machines without first pulling the source from the domain... not a good idea.