How to key in my admin password without a discovered keyboard
I recently took my iMac to have a diagnostic and repair job done. That was due to the computer malfunctioning. When I got home and started the Mac, however, my admin password is required.
The problem is, the Mac cannot discover the keyboard. I cannot get to system preference, because I am unable to
key in the required password.
How can I by pass the password to pair the Keyboard?
iMac, iOS 9.2.1