Due to problems with Protection Engine, being used by Symantec Protection for Sharepoint Servers, the administrator uninstalled Protection Engine then attempted to reinstall it. During the installation it would fail with the following message:
Product: Symantec Protection Engine -- Error 1923.Service Symantec Protection Engine (symcscan) could not be installed. Verify that you have sufficient privileges to install system services.
The installation would go no further.
Release : 8.2.2
The registry entry for the symcscan service was never removed by the uninstall process and it was blocking the ensuing installation process' attempt to create the service and start it.