Your Mac shows an Apple logo when it finds your local startup disk, which is a startup disk built into your Mac or directly connected to your Mac. As startup continues, you should see a progress bar, with or without the Apple logo. This screen might alternate with a blank screen several times.
If you're installing macOS, the Apple logo or progress bar might remain onscreen for much longer than usual after your Mac restarts. As installation continues, the progress bar might move slowly and pause for long periods. That's why Apple recommends beginning macOS installation in the evening—so that it can complete overnight, if needed.
If you feel that you've waited long enough to know that your Mac is stuck on this screen, follow these steps.
- Press and hold the power button for up to 10 seconds, until your Mac turns off.
- Try using safe mode to identify the issue.
- If the issue persists, unplug all accessories from your Mac, including printers, drives, USB hubs, and other nonessential devices. (You could have an issue with one or more of those devices or their cables.) Once more, press and hold the power button for 10 seconds, then press it again to turn your Mac back on.
- If the issue persists, turn off your Mac again, then turn it back on and immediately press and hold Command (⌘) and R to start up from macOS Recovery.
- While in macOS Recovery, use Disk Utility to repair your startup disk.
- If you still need help, please contact Apple Support.