You receive the following error message when installing or re-installing the WFBS-SVC Agent:
There is already an agent installed on your computer.
This problem happens when there is an existing WFBS-SVC Agent in your computer.
To resolve the issue, uninstall the Agent. Refer to the following KB article for the procedure: Uninstalling Worry-Free Business Security Services (WFBS-SVC) Agents.