In Windows 8.1, when you click on the Start Menu, there is a down arrow to see the complete set of program icons, instead of just the ones pinned on the Start Menu. I found some for an old application I had already uninstalled that did not clean up after itself. The right-click uninstall context menu option only opened the Control Panel -> Programs -> Programs and Features selection, which no longer had the app in question.
What I found was that if I chose the right-click, Open file location on the icon, it brought me to the place where shortcut icons are kept.
On my installation of Windows 8.1, it was in
folder, where MYUSERLOGINID is my actual user login ID.
After I deleted the folders with the old program names, the icons were gone.