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If the question mark appears only momentarily before your Mac starts up normally: Best free digital painting software.
From a security standpoint, using the latest version of macOS—the Mac operating system—is always preferred. However, if your Mac is several years old, there's a good chance that the current version of macOS won't run on your Mac; Apple drops support for Mac models that it declares to be vintage or obsolete. Officially, the operating system that was available on that Mac at the time that you bought it is the oldest version of macOS that can run on that Mac. It's likely that an older OS won't include. How to lock in mac. Cia tradecraft manual.
- Reset NVRAM.
- Make sure that your preferred startup disk is selected in Startup Disk preferences.
If the question mark persists, follow these steps:
What Version Of MacOS Can My Mac Run? - Macworld UK
- Press and hold the power button on your Mac for up to 10 seconds, until your Mac turns off.
- Turn on your Mac 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 Disk Utility found no errors or repaired all errors, reinstall macOS.
- If you still need help, please contact Apple Support.