CommonName is marketed as a 'keywords' service, allowing one to enter simple names insatead of URLs.
After its original release, the software has become a complicated (and sometimes buggy) search-hijacker and adware, aggressively bundled with many third-party apps.
Manual removal
Each successive variant of CommonName gets harder to remove by hand. Variants with an LSP (Mib, Zenet, Winnet) are particularly tricky: do not try to delete them by just deleting the files. If you manage to delete the LSP you will lose network connectivity.
CommonName/Comwiz
This variant cannot be manually uninstalled from the normal desktop. You have to boot Windows without letting the two self-restoring processes start up.
On Windows NT/2000/XP/2003, you can do this by pressing F8 just before Windows XP starts loading and choosing "Safe Mode". Open the 'Program Files' folder and delete the 'CommonName' folder inside it.
On Windows 95/98/Me, you will have to boot to DOS to do it, and enter the commands:
cd "\Program Files"
deltree /Y CommonName
This is a 'dirty' way of uninstalling the software, leaving behind a bit of a mess. If you like you can clear up by deleting the registry keys mentioned in the instructions fro CommonName/Agent.