apple bluetooth keyboard freezes at login on macOS sierra
i can't type my password in at login it acts like a button is being hold down and then freezes up.
Is this an imac with wireless keyboard and trackpad? If so try turning off both keyboard and trackpad then just turn the keyboard back on and leave the trackpad switched off.
On my (and others) iMacs the trackpad seems to actively mess up the keyboard. I cannot use mine without making keyboard act up, with it off I have no problems at all.