Pole target twisting mesh when weights are assigned

So I have made rigs and Parented meshes to them with weights many time. This is the first time that giving the arm Kinematics and a pole target twists the mesh when I adjust the pole angle of the Inverse Kinematic constraint.
How do I fix this?

There is one particular angle where it won’t twist the mesh. Use that angle. Don’t change that angle after you find it.

I don’t really under stand what you mean. In order to make the pole angle the same rotation as it is before applying the constraint I have to do 180 degrees because the constrait moved it around to face the other way

Then use 180 degrees. That’s fine.

I’ve seen some people have the misunderstanding that you’re supposed to animate the pole angle. You’re not. You’re supposed to move the pole target after setting the pole angle, and leave the pole angle alone. If you were thinking you’re supposed to animate the pole angle, then yeah, 180 degrees would be a problem. It wouldn’t interpolate properly. But you’re not supposed to animate it, so it’s not a problem.

If, for whatever reason, 180 degrees works, but you really don’t like that, then mirror the pole target across the first bone of the IK chain and set the angle to 0. (Or, add 180 degrees to the roll of the first bone of the IK chain, and adjust IK angle limits as necessary based on that.)

Sorry I read your answer like five times and even went into my project to figure out what you meant but I still have no idea.
The thing is I had to adjust the pole angle on the IK bone on the leg and it didn’t twist the mesh all up. In fact if I didn’t adjust the pole angle it was twist by default. Why is the IK bone on the arms acting differently from the one on the legs?

Because those bones have a different roll, or because the pole target is in a different place.

You don’t have to understand. You said the angle is right when you set the pole angle to 180. So set it to 180. That’s the solution.

Is there another problem after doing that? Okay, what’s the problem? We can handle it, whatever it is.

Well when I set the pole target angle to 180 degrees so it is bent in the same direction as it would be with out the IK constraint applied the mesh twists around with the rotation.
I also just noticed that the right arm(The one I have been talking about so far was the left) is rotated the right way at default zero but the mesh is already twisted unless I change the rotation.
I’m really lost now, all the IK chains are behaving differently
Maybe I should upload my project file so you can look at it

So 180 degrees pole angle doesn’t give you the same rotation as it is without the constraint? Then 180 degrees isn’t the right angle. (For that particular bone.)

You should upload a file. That will always make things simpler.

I figured it out, though I’m not sure what I did exactly.