Unspecified error occurred please check the logs for more information

Hey Guys,

Every time I updated the LOL to 33% or 99% everytime there will always be information of "unspecified error occurred please check the logs for more information", my computer is the Macbook Pro 2013 with Retina,about half a month ago,I played the game very well, then for some reason, my girlfriend deleted the game :( ,now I would like to re-install it but never be updated. I hope someone can help me Thanks a lot.