Upgrade to high Sierra failed, now can't start up or even boot in safe or recovery mode or anything. I get the start up chime & woosh but then nothing

Sorry but none of the suggestions on this board worked for me and I'm still stuck on the installation process.

Are you still having this issue? Mine has just started doing this

I have the same problem! Looking for an answer

Has anyone managed to resolve this issue with Mac Sierra? Tried everything mentioned but no progress. I live in Zambia so getting my MacBook to a professional is extremely difficult.

Has anyone considered booting from a CCC (Carbon Copy Clone) of pre problem.

Man I have had the same issue. Just updated my work computer and it crashed my system. Thanks apple. Two thumbs down man

I tried on a clean install of High Sierra made on friends MacBook. Worked on his, not on mine. I have MBP early 2011

I got stuck upgrading the high Sierra can’t recover

Same here, flashing question mark. I guess I'm heading to apple store in the morning...

Did the store ask you for payment?

Reinstall OS X by booting from the Recovery HD using the Command and R keys. When the Utility Menu appears select Reinstall OS X then click on the Continue button.

this worked like a charm.

Update: Called their help desk, and they managed to talk me off the ledge. It's installing now, so fingers crossed.

Try downloading and reinstall the firmware.

Kappy! I’m having a similar issue! Please help!