You’ve tried entering your password, but it doesn’t work. Should you try guessing? As that imposes increasing waiting times of up to 8 hours, maybe not. Try this instead.
Recovery Assistant
If you’re lucky, it should restart into Recovery Assistant. Otherwise advice on how to manage a boot loop or freeze, and how to disable 3rd party kernel extensions.
We’re running out of panaceas. Resetting NVRAM and SMC, repairing permissions, installing the Combo updater. or re-installing macOS, are vanishing fast. Is Recovery Assistant the new panacea?
An enhancement to Recovery intended to fix Macs that don’t start up correctly. Also available in Recovery mode.
The Eclectic Light Company 