faXcooL.exe is a Hack tool used for disabling Windows Genuine Advantage Checks, it is what they call a "Remove WAT" tool, if your computer found this, either you installed a pirated version of Windows or whoever installed Windows on your computer used a pirated copy. Or you or someone downloaded the tool to Remove WAT, or you downloaded it on accident, either way it's not going to harm your computer, just don't run it if you have a legit copy of windows.
-Sean