When will comodo shut itself down?

On two occasions I have returned to the computer to find a message (with the message box showing a Comodo logo) indicating my firewall has encountered a problem and must shut down. Two choices allowed, I chose “Debug” The Debug choice notes a memory reference that “could not be read.”

Logs do not record any incident.

I am running Norton AV with Comodo 2.

Unfortunately, I did not record the memory referenced or take a screen shot to share. Any idea what this behavior indicates? Under what circumstances might Comodo politely shut down?