My iMac will not start up says too many corpses

Learn what to do:

• If your Mac starts up to an Apple logo or progress bar - Apple Support

https://support.apple.com/en-us/HT207019

"Your Mac shows an Apple logo when it finds your local startup disk, then

shows a progress bar as the macOS startup or installation process continues."

[With curative ideas through out article and links toward the end.]

Good luck & happy computing!🌻🐝

See if the following article can help: If your Mac doesn't start up all the way - Apple Support

Check If your Mac doesn't start up all the way - Apple Support

Good luck!