So lets work out the issues you are facing here. When your boot drive messes up you can face a few different issues trying to recover things. The first one is trying to boot up under an external drive here we need to get to the Startup Manager within your systems firmware to select the alternate drive. Hold the '''Option (⌥)''' key then you can select your external drive without removing your internal drive!
OK, how to fix your internal drive with your external drive now the boot drive run Disk Utility to check it out under First Aid. Did you get any errors? You might want to run it a second time to be sure you got all of the errors.
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OK, how to fix your internal drive with your external drive now the boot drive run Disk Utility to check it out under First Aid. Did you get any errors? You might want to run it a second time to be sure you got all of the errors. Do make sure you’ve using the same OS version on your external as Apple has changed the file system under High Sierra & Mojave to APFS from HFS+. Older Sierra and back boot drives won’t have the ability to see this newer file system.
How full is your drive?? If you don’t have much free space you’ll want to copy off anything you can to free up 1/4 of the drive. I would also take the time to make a backup to be safe.
Then we want to re-install the OS running the OS installer using the same OS your system is running. If you don’t have it you can get a fresh copy from the Apps Store looking at the Purchased listing for it.
What I like to do is make an OS installed USB thumb drive [https://www.macworld.com/article/3092900/how-to-create-a-bootable-macos-sierra-installer-drive.html|How to create a bootable macOS Sierra installer drive]
So lets work out the issues you are facing here. When your boot drive messes up you can face a few different issues trying to recover things. The first one is trying to boot up under an external drive here we need to get to the Startup Manager within your systems firmware to select the alternate drive. Hold the '''Option (⌥)''' key then you can select your external drive without removing your internal drive!
OK, how to fix your internal drive with your external drive now the boot drive run Disk Utility to check it out under First Aid. Did you get any errors? You might want to run it a second time to be sure you got all of the errors.
How full is your drive?? If you don’t have much free space you’ll want to copy off anything you can to free up 1/4 of the drive. I would also take the time to make a backup to be safe.
Then we want to re-install the OS running the OS installer using the same OS your system is running. If you don’t have it you can get a fresh copy from the Apps Store looking at the Purchased listing for it.
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What I like to do is make an OS installed USB thumb drive [https://www.macworld.com/article/3092900/how-to-create-a-bootable-macos-sierra-installer-drive.html|'''How to create a bootable macOS Sierra installer drive]'''
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What I like to do is make an OS installed USB thumb drive [https://www.macworld.com/article/3092900/how-to-create-a-bootable-macos-sierra-installer-drive.html|How to create a bootable macOS Sierra installer drive]
So lets work out the issues you are facing here. When your boot drive messes up you can face a few different issues trying to recover things. The first one is trying to boot up under an external drive here we need to get to the Startup Manager within your systems firmware to select the alternate drive. Hold the '''Option (⌥)''' key then you can select your external drive without removing your internal drive!
OK, how to fix your internal drive with your external drive now the boot drive run Disk Utility to check it out under First Aid. Did you get any errors? You might want to run it a second time to be sure you got all of the errors.
How full is your drive?? If you don’t have much free space you’ll want to copy off anything you can to free up 1/4 of the drive. I would also take the time to make a backup to be safe.
Then we want to re-install the OS running the OS installer using the same OS your system is running. If you don’t have it you can get a fresh copy from the Apps Store looking at the Purchased listing for it.
-
What I like to do is make an OS installed USB thumb drive
+
What I like to do is make an OS installed USB thumb drive [https://www.macworld.com/article/3092900/how-to-create-a-bootable-macos-sierra-installer-drive.html|'''How to create a bootable macOS Sierra installer drive]'''
So lets work out the issues you are facing here. When your boot drive messes up you can face a few different issues trying to recover things. The first one is trying to boot up under an external drive here we need to get to the Startup Manager within your systems firmware to select the alternate drive. Hold the '''Option (⌥)''' key then you can select your external drive without removing your internal drive!
Reference: [https://support.apple.com/en-us/HT201255|Mac startup key combinations]
OK, how to fix your internal drive with your external drive now the boot drive run Disk Utility to check it out under First Aid. Did you get any errors? You might want to run it a second time to be sure you got all of the errors.
How full is your drive?? If you don’t have much free space you’ll want to copy off anything you can to free up 1/4 of the drive. I would also take the time to make a backup to be safe.
Then we want to re-install the OS running the OS installer using the same OS your system is running. If you don’t have it you can get a fresh copy from the Apps Store looking at the Purchased listing for it.
What I like to do is make an OS installed USB thumb drive