I too am having an issue. My WIndows 10 Update refuses to continue to update unless I uninstall League of Legends. I selected the uninstall button so it could continue, but after it's been uninstalled it is still asking for moar League uninstall. I thought that since I couldn't find the files, I'd just reinstall the game, then uninstall it through Control Panel instead of their Windows Updater (because it obviously didn't do something right). When I installed the game, the client-updater crashed and I cannot get it to install the files for the full game so I can uninstall it. So I now have no idea how to fix this issue.