What is it?
Creative Software - cthelper.exe

What does it do?
cthelper.exe - This is bundled with Creative software. It is designed to help third party developer build plugins and software to work alongside creatives software and hardware packages. If you have something like a Creative Labs soundcard in your system this file is OK. If you don't then you've got a problem.

Virus Precautions:
You'll want to keep an eye on this google search for any known viruses. The normal location of cthelper.exe is C:WINDOWSsystem32CTHELPER.EXE