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kbpereira Author

Level 1

8 points

OS X Base System is locked?

I was having problems with my iMac, when I decided to clean up abd restore as factory seetings.

Now, I am having a problem which says mt OS X Base System, that the disk is locked. What do I do?

iMac 27″, 10.12

Posted on Mar 17, 2021 3:06 PM

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Top-ranking reply

Level 8

46,098 points

Posted on Mar 17, 2021 3:20 PM

Somehow, you did not erase your disk correctly. Follow these steps:

Once you are in macOS Recovery, verify you are connected to WiFi in the top right corner.
Quit the Installer
Go to Disk Utility.
Select "View" in the toolbar > "Show All Devices".
Select your main hard drive. This will either be "APPLE SSD...", "APPLE HDD...", or "Fusion Drive". It is the non-indented drive.
Click Erase, and input the following exactly:
Name: Macintosh HD
Format: Mac OS Extended (Journaled)
Scheme: GUID Partition Map (if shown)
Click Erase
Quit Disk Utility
Go to the reinstall macOS app.
Follow the prompts, and install on Macintosh HD.

Cheers,

Jack

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7 replies

Top-ranking reply

Level 8

46,098 points

Mar 17, 2021 3:20 PM in response to kbpereira

Somehow, you did not erase your disk correctly. Follow these steps:

Once you are in macOS Recovery, verify you are connected to WiFi in the top right corner.
Quit the Installer
Go to Disk Utility.
Select "View" in the toolbar > "Show All Devices".
Select your main hard drive. This will either be "APPLE SSD...", "APPLE HDD...", or "Fusion Drive". It is the non-indented drive.
Click Erase, and input the following exactly:
Name: Macintosh HD
Format: Mac OS Extended (Journaled)
Scheme: GUID Partition Map (if shown)
Click Erase
Quit Disk Utility
Go to the reinstall macOS app.
Follow the prompts, and install on Macintosh HD.

Cheers,

Jack

Reply

Level 10

84,472 points

Mar 17, 2021 3:23 PM in response to kbpereira

If that is the only place that is seen by the macOS installer, then the drive is not formatted properly or the drive is bad.

see > https://support.apple.com/guide/mac-help/erase-and-reinstall-macos-mh27903/mac

and/or > https://support.apple.com/en-us/HT204904

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kbpereira Author

Level 1

8 points

Mar 18, 2021 5:16 PM in response to Jack-19

Only today I was able to do something, as the progress bar it was frozen.

but still not sucessful, I followed all the directions you have fiven and this is what I see now.

the APP Store download could not start because it has already been downloaded too many times.

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kbpereira Author

Level 1

8 points

Mar 18, 2021 6:38 PM in response to Jack-19

Actually you have helped me. Because I just got the message after following the steps you have passed out to me.

I just researched for the message and founded the instruction.

Thanks so much for your help, be blessed.

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Level 8

46,098 points

Mar 18, 2021 5:18 PM in response to kbpereira

What year is the iMac?

Cheers,

Jack

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kbpereira Author

Level 1

8 points

Mar 18, 2021 6:08 PM in response to Jack-19

Late 2013.

I finally installed MacOS Catalina.

Previously I was pressing Command + R during startup.

I Finally pressed Command + Option + R and it installed Catalina on my Mac.

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Level 8

46,098 points

Mar 18, 2021 6:10 PM in response to kbpereira

That’s why I asked for the year. That was the next step I was going to have you try.

Cheers,

Jack

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OS X Base System is locked?

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