Chosen Solution
The power cord was pulled out of the wall socket while my iMac was still running. Now it will not boot up past the black screen and white logo with bar. It just sits there doing nothing at that point.
It sounds like your drive has a file or two which have become corrupted as it was in the middle of updating the file in mid-operation. Lets see if the system can boot up under Safe Mode. Hold the ‘Shift’ Key when you restart your system was it able to cleanly start up then? If not, We’ll need to then get into the systems recovery partition and run Disk Utility from it. Reference: Mac startup key combinations
