Windows NT Evaluation Process

I’m getting a in the event log on a remote PDC in system processes that refers to Windows NT Evaluation Process. It reads as follows,The evaluation period for this installation of Windows NT has expired. This system will shut down in 1 hour. To restore access to this installation, please upgrade this installation using a licensed distribution of this product. As far as I know it has a licensed copy of NT Sever on it.Is this a bug and if so is there any easy fix? Any thoughts