Rigging problem

When I added my poletarget for my IK chain, it stopped solving and now just sticks straight out, anyone know what’s going on?

http://privatepaste.com/0d1d0axC9B

What’s even weirder is it’ll only right itself after I give the IK bone any kind of rotation- but I’m looking at other rigs that have zero’ed out rotation, so I have no idea what’s gong on.

No one knows?

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