When you attempt to uninstall KeyPad, it must make sure that Internet Explorer is not running so that it can remove the toolbar. However, it is possible to have Internet Explorer running in the background without showing a window.

When this occurs, you can kill the Internet Explorer by opening the task manager (usually accessed through ctrl+alt+delete), clicking on the processes tab, and then find iexplore.exe in the list of processes). Click on the iexplore.exe process and then click "End Process".