How do I ACTUALLY keep this from popping up?

(Thought I originally posted here, didn't realize it was in 'ask the community'...D'OH!)

I have already Google'd what SHOULD be the correct answer and still this issue persists despite having followed instructions to a 'T'. I have, actually, followed the steps necessary to stop OTHER programs from prompting this message in the past and it worked for them but League of Legends is such an anomaly that it outright ignores the settings altogether.

I've even removed League from the list entirely and re-added it. I've re-installed the client altogether. I've done so many variations of how to possibly fiddle with it in case settings are not actually being saved but still this stupid box mocks me.

This problem has persisted since even before the updated client. It doesn't appear to actually hamper my connection to the game (assuming I even load in at all, thank you 100% load screen bug that has yet to be fixed) but I do worry if it does affect SOMETHING I am unaware of.