Norton not completing setup, Allow Button in iMac not working even with Tips (tab, spacebar etc....)
the only way you can hit allow is from that computer's mouse, while in front of that computer.  if you try with teamviewer, ARD, vnc, etc, it will fail.  if you're clicking it "in person", perhaps it's confused by some periph or needs uninstall/reinstall.

as a support person, this is a big stumbling block with our users.