I have a strange question to throw out there. I have a server that stopped comms to my SEPM servers. When investigating the day it stopped comms was the day that it ran out of disk space. The issue being that its the data drive that is out of space when dosent hold either the OS or the SEP client install so should it be happening ?
If SEP is installed correctly, it should not stop communicating even if it runs out of space, this is a separate problem.
Please run the symhelp tool on it to help in troubleshooting errors:
Troubleshooting computer issues with the Symantec Help support tool
SEP client commuication & SEP client not updating are two different things. If SEP installed drive is out of space then it will stop latest definitions downoad.
Make some free space to run the applications without any issue.