Well, I found one thing different than how install it: When you are about to put the mod into the mod folder,I take the pixelmon 2.3.1 folder, and put it in the mods folder, Instead of opening the file and putting in the .minecraft. That's just what I do. I hope it helps?
Also, try a new server.
I did exactly this but then everytime i try to pick a pixelmon it crashes
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I did exactly this but then everytime i try to pick a pixelmon it crashes
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