Bug splat every game in loading screen ALT+TAB

every time when i start a game and i chose my champ and go to loading screen .. than i try to ALT+TAB but than comes a bug-splat than i cant reconnect anymore til i go to "League of Legends Admin " and than i need to update cuz i miss files for no reason... and now for the third time i get a leaverbuster cuz my team remake and i lose much of lp too. I thought there is something wrong with my pc but my friend has also. Fix pls .. and rip my lp And sorry for my bad English