Note that many websites have their own advertising, unrelated to adware.
Displays popup advertisements and drops icons on desktop containing shortcuts to various websites.
Some of the URL's dropped on the desktop are very generic in nature, e.g. Games.url
To clean these, first run XCleaner on the machine and remove all the components that it detects and reboot the machine.
After reboot, manually remove the remaining URL's that might be there on the desktop.