Profiler serial moments stopped on Friday, at 2017-01-20,09:58. I checked on the profiler PC with VNC, but there was nothing in the event logs to specifically indicate a reboot or a pop error. In the application event log, rsyncserver and norton ghost started up around 10:00:06. In the system event log, there appears to be a windows startup message at 09:59:53. So I think the PC rebooted, but I cannot find out why.
After investigating the logs, I tried restarting POP with the desktop icon. It counted down, and then nothing happened, the VNC screen did not change, and no moments data were recorded by the data manager. Also, I could no longer connect with VNC.
While connected over VNC, I added the data manager (192.168.0.56) as the primary time server to symmtime.
So yesterday, 2017-01-21 around noon, I visited the profiler site. The profiler PC was not hung, but POP was not running, and the VNC server had stopped with an error dialog. So I restarted POP with the desktop icon. Later I realized I had not restarted VNC, so I quit POP, restarted VNC from the Control Panel->Admin Tools->Services dialog, then restarted POP. When I left, everything was working.
I've created a JIRA issue for the intermittent reboots: https://jira.eol.ucar.edu/browse/ISS-554.