Patching of Microsoft defender keeps failing The latest update for Microsoft Defender (1.429.453.0) with error message "Another version of this product is already installed. Installation of this version cannot continue. To configure or remove the existing version of this product, use Add/Remove Programs on the Control Panel."  

There is nothing in Add/Remove Programs.  I'm pretty sure you can't just uninstall Microsoft Defender or its definitions.  

Patch ID 400009

Bulletin AV-FCS03

The latest update for Microsoft Defender (1.429.453.0)

Any help with this would be appreciated.