Boot Error after Windows update - Black screen with Top left corner blinking cursor after power on

[221baker]

error observed after windows update.

on reboot instead of coming up to login screen.

It beeps once and then I get a black screen with flashing/blinking cursor in top left corner.

not really a cursor so much as a blinking underscore.

machine is Z230 SFF

[221baker · Accepted solution]

turns out the problem was no keyboard connected.

With power on password set in bios - the flashing cursor is where the boot process stops if no keyboard is found.