PROBLEMS LAUNCHING NEW CLIENT

I constantly have trouble getting the new client to launch. Often when I click the launcher the league of legends icon pops up but then nothing happens, or the client window will pop up, but will be whited out so that I never get to the login screen. This also crashes the client when returning to the post-game screen (quit client during game setting on). This happens literally 50% of the time I click the launcher/ finish a game, and the only solution is usually to reboot my computer. Riot Help Please.