This happens most likely when an Antivirus software blocks, and/or puts the executable to the quarantine due to a false-positive detection of the WebMonitor executable.
In such case, RevCode advice you to create an exception for the WebMonitor executable with your Antivirus software, or simply disable it in order to prevent any unwanted interference.
In addition to that, the WebMonitor client for PC requires that the system on which the WebMonitor for PC executable/.exe is installed on requires a physical mouse movement in order to be activated the very first time. This is a security mechanism implemented by Revcode to avoid abuse of our services, i.e. by filtering out automatic installations or the WebMonitor .exe.