This may not seem to be a major problem, however after a few times of this happening it starts to get annoying to task manager close it. I tried waiting for the client to close by itself for a few minutes, but it just freezes.

yeah i can confirm however this alt + f4 works. can we get a red to look at his?

This was still happening to me today. Just to update.

Guys, instead of open task manager to kill it, right click the program in the taskbar and click close. I know it a bit of a hassle but, bugs are bugs.

Same.

There isn't probably a need to confirm anymore, but I would like to confirm :P

same thing happened to me on mac client...went to change summoner name and it got stuck trying to sign off...couldn't force quit or do a regular shut down so i had to force shut down my computer.

It happen to me when i play 1 game or more (not spectate cause i try). I can't turn it off.
If i Log in and not playing, i can turn it off. Buf try 1 custom or any game, no matter how long. It bugged and can't turn off
And when i open my PC First run LOLPBE. I can't login no matter how i wait. I have to turn the LOLPBE off and do a again. If you want to, i can record the error for u guy

It does not always happen though, at least in my case.

Still happening, only way to actually "log out" is to force close the client with Task Manager.