So I recently installed LoL on my gf's computer.
She finished patching, logged on once as me, and then logged out entirely. Sometime later, with no apparent LoL process over, this error popped up.
She was able to login a second time with no problem, and the error didn't reappear.
So all in all pretty minor, just wanted to document it.
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Jozrael ?? QA Analyst