Chosen Solution
I tried re-installing High Sierra but forgot to wipe the HDD. After rebooting and trying to re-install with a wipe, the imac turns on, plays the start up chime, then every 3 seconds later it will play the chime again. The screen is white/grey (hard to tell as the brightness seems to be all the way down) It is not chiming every 5 seconds . No keyboard commands work. It is like its stuck in a loop. Tested other keyboards. Any ideas on how to fix this issue?
Umm… You probably wiped more than you had to. It sounds as though you have wiped the MacOS proprietary systems (or at least some of them) This has effectively killed your Mac as it has no idea what to do or how to do anything. You could A. download a pirated file of Mac Proprietary systems (VERY rare to find as it is the same file that will turn a windows computer into a Macintosh [hackintosh]) or B. spend a little money and have it fixed by Apple.
