The PC Tools Threat Removal Tool aims to remove malware that may prevent PC Tools' antivirus software from being installed.
If you're having trouble installing a PC Tools security application, then (or perhaps something from another manufacturer), then it's worth downloading the program to give it a try.
There's no complexity here, no setup required, and no lengthy scanning process: just download and unzip the Removal Tool, launch its executable, click Start Scan, and you'll have a verdict on your system health in a surprisingly short time (some 12 seconds on our test PC).
You can then keep the program around to run additional on-demand scans whenever you like. Keep in mind that this isn't a generic malware hunter, though: as the authors say, it concentrates specifically on malware families that "block, prevent, or terminate PC Tools' security software installers" only. Other threats won't be detected, so this is no substitute for a more thorough antivirus package.