Why won't the PolicyPak services start, with an error like (or similar to) "Verify that you have sufficient privileges to start system services."?

If you get an error while starting the Netwrix PolicyPak services, such as this…

Product: Policypak Client-Side Extension -- Error 1920. Service Policypak ' Watcher Service (64-bit)' (PPWatcherSvc64) failed to start. Verify that you have sufficient privileges to start system services.

It's likely your Antivirus is preventing PolicyPak from operating. We know at least Carbon Black will prevent PolicyPak from running unless it's exempted.

For more information How must I configure my Anti-virus or system-level software to work with PolicyPak CSE?.

Example of error and results in Event log: