After creating an EMDI and adding it as an optional validator to a DI policy rule, no detection occurs.
This is applicable to version 15.7.x, 15.8.x and 16.0
EMDI is not turned on by default.
The EMDI index does not publish to the Endpoint Agent unless the parameter has been set in the Agent's Detection Server's Protect.properties file.
Verify that the parameter EMDI.EnabledOnAgents = true in the Protect.properties file on each endpoint server.
If this setting is still false, edit the protect.properties file and set it to true.
This property will be picked up by the agent after your polling time has expired (default is 15 minutes.)
This is applicable for 15.7.x and 15.8.x as outlined in the EDMI troubleshooting section of online help.