Won't start

Ok, so when I opened league the whole thing went black and I couldn't even click it down, so the only way to remove it was to remove league. Once I removed league I re downloaded it and it wont ever load up to a 100 pro cent, it ALWAYS said bugsplat or "An error accord, please try restarting" This has been going on for three days and i've tried it at LEAST 15 times. Please help me.