[ERROR] Unable to verify source for expansion [C:\Riot Games\League of Legends\Air\assets\locale\resources-en_GB.swf]
Right click on this link -> save link as -> place it in C:\Riot Games\League of Legends\Air\assets\locale\
It says that this file doesnt have any program asociated to do this action
Do not open the file, just save it in the league of legends\air\assets\locale folder and try to run the game again
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