PvZ BFN : Failed To Download Patch (PC, Founder's Edition)

@TetraStar7  Hello. 

In addition to uninstalling the game, uninstall Origin as well. 

http://help.ea.com/en/article/manually-uninstalling-origin/

Then you can try to fix issues with this:

http://help.ea.com/en/article/how-to-use-ccleaner-to-fix-pc-issues/

Follow the steps in this link. 

Then preform Clean Boot:

Clean Boot: https://help.ea.com/en/help/faq/how-to-clean-boot-your-pc/

Download latest version of the Origin here: 

https://www.origin.com/en-gb/download

Open Origin as Administrator and try to download the update.

Your games won't be uninstalled after uninstalling Origin. 

If it doesn't work: 

Create new a new Temporary Windows User account and see if you're able to launch the Game under that Profile.

I hope it'll help you with solving the problem.