I have a utility that tells me the unistall string, but you can usually find the {Code} it in your registry.
Depending on how it was installed, Look in the registry in one of the following places and search for Ringcentral (Or whatever program) and copy the {Code}.
You may also be able to find the {Code} in the desktop shortcut (If you haven't replaced it with one that doesn't break the taskbar icon with each update like I have.) The problem with the default shortcut is that it gets the icon from the Installer folder, which might actually be helpful for you in this instance. If you Right Click - Properties on the shortcut and click the Shortcut tab and then the Change Icon button, it should reveal the {Code} in the Installer folder.
The reason it breaks the Taskbar icon each time you install a new version is the folder that contains the Icon is removed with each new version. My shortcut gets the icon from the program files "exe" instead of the unique {Code} installer folder "ico" file.