Could not update ThreatFire to 4.1.0

I recently tried to update ThreatFire 4.0.0.10 to its newest version, but it failed. I have a TF 4.1.0 ready for installation. I deleted my present version of TF, and do a fresh install of 4.1.0. However, when trying to install TF 4.1.0, I received a message stating that there was another copy of ThreatFire that was already running so I was not able to install TF 4.1.0.
The next thing I did was to perform a reboot and then install TF 4.0.0.10. I am thinking that if I will try to re-install the older version, I could be able to remove it correctly. But I encountered the same exact error.

Setup
This installation of ThreatFire will not proceed because we have detected that another instance of ThreatFire is already installed on this computer. You either have a different version of ThreatFire installed or you have a bundled version of ThreatFire included as part of another security product. A sample of bundled instance would be the Behavior Guard in PC Tools Internet Security Suite. Only one instance of ThreatFire, whether a full or bundled version, can be installed at any given time. If you wish to change your current ThreatFire installation, please check your installed programs through the Control Panel, Add or Remove Programs. For further assistance, please feel free to contact support at https://us.norton.com/.
