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Problem with Samsung T7 External SSD

I am on macOS 10.15.7 (Catalina). It is a Macbook Pro 16".

I am not a beginner.

I am trying to clone my HD on my new Samsung T7 external SSD. Format: APFS. Not encrypted. No password. I am trying it with Carbon Copy Cloner and SuperDuper.

No matter what I do, it fails just seconds after I press "Clone". It stops. No files are transferred.

CCC says "The APFS replication procedure failed". On their site, they say they do not know what causes this.

When I manually drag and drop files on the T7, it works. So, the drive is OK. I just cannot make a copy of my HD on it.

I tested it on my wife's Macbook Pro. Same problem. Any help?

Posted on Nov 10, 2020 1:41 AM

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3 replies

Nov 10, 2020 3:04 AM in response to Bento de Espinosa

CCC does not work with APFS formatted drives, reformat the drive as Mac OS Extended using Disk Utility (located in Applications > Utilities folders.

You must have View show all devices selected in the view menu to erase the drive.

Nov 10, 2020 4:12 AM in response to Gary Scotland

Thanks, but that is not the problem, since, under "Preparing your destination disk for an installation of macOS", CCC's site does state: "Mojave and Catalina: Choose APFS if you are backing up your startup disk or another installation of macOS".

Nov 10, 2020 6:13 AM in response to Bento de Espinosa

I said "I am not a beginner", but more advanced users can be fools too.

My version of CCC was not the latest one. I upgraded it to the latest version, and now the problem is gone. Cloning works.

Lesson learned: when you have problems with a software, first upgrade to its latest version. Sometimes, the problem gets solved just by upgrading.

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Problem with Samsung T7 External SSD