can't log into servers cause 1.11 is a dick

When I logged out of 1.11 snapshot 16w40a to go to 1.10.2 to play on a server, it said "Failed to login: Invalid Session(Try restarting your game)".

I tried restarting my game and this same thing happened again!

I ended up doing it like 5 times and it still didnt work.

However I deleted the 1.11 Snapshot version folders and it solved it
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But when i redid all of whats up there, it jammed up and it didnt work

I tried over and over again trying to delete all traces of 1.11 and it still didn't work.

What the hell mojang????

Give me answers cause this is bullshit.