The agent log shows:
============================== Agent inactivated ==============================
Solved! Go to Solution.
Agents that have been manually deactivated by the user (= monitoring off) can be reactivated as follows:
1. Go to "Hosts" and select a timeframe that covers the time when it was deactivated
2. Choose the filter "Monitoring disabled" in the left menu
3. Now inactivated agents are showing up and can be selected; to enable monitoring, go to "Settings" and turn monitoring on