My Mac won’t start up. It was unplugged during a shutdown, and now it restarts over and over. I’ve tried holding command+option+p+r. Also I tried booting up in safe mode by holding shift on startup and nothing happens. Can someone point me in the right direction or at least tell me what the problem is?
iMac 27″, macOS 10.12
That sounds like a hardware failure such as the HD failing. However, please first try the steps If your Mac won't turn on or start up and also https://support.apple.com/en-us/HT207019 If both fail then the next step is to repair or replace the computer. If the computer is not vintage you can take it to your local AASP to be repaired. AASP Locator
As you do not say what model year the computer is we cannot tell you if it is obsolete or not. Apple has made 27" iMacs since late 2009. To learn if your iMac is considered vintage by Apple please click https://support.apple.com/en-us/HT201624
That sounds like a hardware failure such as the HD failing. However, please first try the steps If your Mac won't turn on or start up and also https://support.apple.com/en-us/HT207019 If both fail then the next step is to repair or replace the computer. If the computer is not vintage you can take it to your local AASP to be repaired. AASP Locator
As you do not say what model year the computer is we cannot tell you if it is obsolete or not. Apple has made 27" iMacs since late 2009. To learn if your iMac is considered vintage by Apple please click https://support.apple.com/en-us/HT201624
I Mac won’t start up. Keeps saying your computer restarted because of a problem
