Symptoms: - SEPM service is running, Manager console is functional, but the logs show consistent connection errors as if the SEPM service is off.
- End user experiences random log-off from the SEPM, or random failure to process policy without a re-start of the SEPM service.
This issue occurs because of a race condition in the TCP/IP driver (Tcpip.sys) on Windows Server 2003 using Service Pack 2. A hotfix is available from Microsoft to address the issue, see Microsoft article:
TCP connections fail intermittently when both endpoints are on the same computer in Windows Server 2003 SP2