Cant play bug

How do i do that? i never dled w.e that is, and i its not on my uninstall programs list, just lightly scanned through riot games folder and dont see anything related

Pando Media Booster was originally made to help patches run through and download more smoothly, therefore when you downloaded league it was required to download with it. Since then Pando company has shut down and the program has been listed as a known virus or malware. You shouldn't fear this malware as it wont steal your bank info and ruin your life or destroy your computer or anything like that, but it has made it that in some cases it refuses to leave. Because of this you have to "manually remove" Pando media booster.

http://www.bncarm.com/how-to-remove-pando-media-booster-the-best-pando-media-booster-removal-guides/

This should help, I would reccomend going through each of these steps, restarting your computer and trying to run. If that doesn't work I would advise you send in a support ticket. It's easy to keep this kind of thing off of your computer, but sometimes it can be a pain to remove.