Detection Server showing ‘Unknown Status’ after performing a fresh install.  Communication is working between the Enforce and Detection Servers.

On the affected detection server check for the file called monitor.timestamp.sslKeyStore 

• In version 15.0 and before this will be in:  \SymantecDLP\Protect\keystore This file is necessary for communication.
• In version 15.1 this will be in: C:\ProgramData\Symantec\Data Loss Prevention\Detection Server\<version>\keystore
• In version 15.5 and greater this will be in: C:\ProgramData\Symantec\Data Loss Prevention\Detection Server\<version>\protect\keystore

  If the file is not present then copy the same from another working detection server and paste it to the affected detection server. Take a backup before you make any changes.

Restart the Vontu Monitor service (or SymantecDLPDetectionService on 15.1 and later)

Note: Ensure to take proper backup of appropriate folders related to keystore before performing any troubleshooting to avoid Data loss.