XP workstation keeps dropping domain user

[Enkrypted]

We are running a 2003 domain with several XP workstations. All of the workstations have no issues except for one of them. When adding the domain user to the local machine administrators group (through control panel>user accounts), everything works fine until the machine is restarted. After a restart, it drops the domain user as a local machine admin and that user has to have me re-add him again. Does anyone know what could be causing that? If more info is needed, let me know. TIA!

Enkrypted
A+

 

[AaronBeau]

I would try running Group Policy Results and determine if there is some group policy applying to that computer or user that is causing that behavior.

 

[Enkrypted]

Group policy is the same for all the users/computers so if it was a GP setting, others would be affected as well.

Enkrypted
A+

 

[cdtech9198]

Remove from the domain then add back.

 

[4elgatofeo]

In TCP settings ip v6 may be set, take the check out, reset adapter and ipconfig
also you may need a VISTA patch from MS