What to do when Time Machine says a verification failed

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Apple

I’ve been a Time Machine skeptic for many years, even though I’ve used it at times (though not lately), and have been writing about how to use it better and control it for that same length of time. That’s because Time Machine lacks much in the way of solving problems when things go wrong. Apple chose that approach for simplicity, but it leaves users in the lurch.

Take the case of Macworld reader Talon, who wrote in after they received a message (and not for the first time) noting:

Time Machine completed a verification of your backups on “Hobson’s Choice AirPort”. To improve reliability, Time Machine must create a new backup for you.

This dialog presents two options: Start New Backup, which removes the entire existing backup history, and Back Up Later, which retains it but stops back ups. This is no real choice at all presented as a choice. Why did the backup become corrupt? Why can’t it be recovered? What is the meaning of life? We don’t know the answer to any of those questions, because Time Machine (and existence itself) is impenetrable. With other backup systems, there’s usually a way to repair, recover, or extract files from a damaged backup.

And, in fact, Apple offers such an option without explaining it in the above dialog box—it’s in macOS help, instead. If you pick Back Up Later, you can still try to retrieve files, by using the regular Time Machine interface. You may have no success, but it’s a possibility at least.

My advice as always is to have multiple backups of any file you want to make sure you have in the future—even if the future is an hour away or tomorrow. One copy is bound to fail, while two at least offer some peace of mind. Some phrase this as “3-2-1”: three copies of your data, two different methods, and one offsite.

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