[daydream]

iMac will not boot after firmware update what to do?
I ran the firmware update for my daughters’ iMac 233 MHz Rev. A (Pull out tray). After running the update the Mac boots up and you see the thermometer going along and then it stops 1/3 of the way.

So is there any fix for a firmware update gone badly?
Could I log into the firmware and type something in that might get it to run?
Accepting any and all ideas except the boat anchor one.

[Eriamjh]

Try booting while holding the 'shift' key (extensions off/safe mode). Perhaps now, some extension or other utility is causing it to hang.