Chosen Solution
I own an iMac with an OS below Catalina. 2 days ago, There was an unwanted shut down by the desktop being unplugged while the computer was restarting in an attempt to download the OS. The screen was black with an Apple Logo like when you wanna start it but after being forcefully unplugged, it won’t turn back on. i read somewhere that mac OS has a mechanism of shutting their system off for 3 days after these kinds of forceful shutdowns. It has only been 2 days now but i’m scared that something else is causing my iMac not being able to start. Does anyone ever have the same problem and has solved it?
OK, let’s clear the latch to see if what you did messed it up. Disconnect the AC power cord, press and hold the power button with nothing connected for a good 15 sec. That should reset SMC (I prefer this method than Apples) Here’s more on resetting SMC How to reset the SMC of your Mac I fear you may have messed up your system by disconnecting the power cord in the middle of a write operation so your drive maybe corrupted! Unlike the older systems your’s has a T2 chip which encrypts your flash storage. I hope you have a good backup as the two times I faced this I had to reformat and install a fresh OS to the drive to get the system running again. Make sure you properly shut down your system before you disconnect the power cord. You may want to invest in a good UPS so if your power goes out you have time to do a proper shutdown (you can even automate this).
