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2460-1785 Author

Level 1

4 points

Erase backup disk

How do I erase old data from my external hard drive?

iMac 21.5″, macOS 10.15

Posted on Jun 9, 2020 8:22 AM

Best reply

WoodPlane

Level 2

303 points

Posted on Jun 9, 2020 1:39 PM

Open Disk Utility (In the Applications/Utilities folder).

Select the disk you want to erase.

Click the erase icon.

Select the level of security you want. Higher security means over-write more often.

Large drive may take a long time.

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Erase backup disk

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