Yes, the IK plug-ins themselves need to be run as administrator.
Don't just click "Run as Administrator" in the pop-up.
You need to right click the .exe, select Properties>Compatibility. Place a check mark int the Privilege Level box.
You should be good to go after that.
I have only had to do this with my IK plug-ins(so far).
It was a lot more effective than the colorful verbage floating around my room 'til I figured it out

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