It goes for a few mega bytes while launching the latest version of the game and then it says "The specified custom log config does not exist." What does it mean.. please help me

I checked the recommended requirements for minecraft and my computer should work pretty well.

While launching another version (1.10.2) it says "Unable to save download. az_AZ.lang"

Please help me.

P.s: Your new launcher is weird I liked the old one better.

Edit: All of them say "Unable to save download. az_AZ.lang"