To find out the specific reason why the IPS engine shows offline, review the system event:

1. Log on to the Deep Security Manager (DSM) console and go to Computers. Find the agent you want to check.

   

   ^{Click the image to enlarge.}

2. Double-click on the agent and open its properties. Navigate to Overview > General, then click Intrusion Prevention Engine Offline to check.

   

   ^{Click the image to enlarge.}

An optional workaround would be to reinstall the IPS feature.

1. Double-click on the agent and open its properties.
2. Go to Overview > Intrusion Prevention, and set Configuration to "Off" then save it.
3. Set Configuration to "On" and save it again.

   

   ^{Click the image to enlarge.}

   

   ^{Click the image to enlarge.}

If the reason is still not found, collect DSA diagnostic package and contact Trend Micro support for help.