You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

What is wrong when preparing backup takes a long time?

Time Machine took all night and did not finish preparing!

MacBook Pro 15″, macOS 11.2

Posted on Sep 18, 2021 1:42 PM

Reply
Question marked as Top-ranking reply

Posted on Sep 20, 2021 10:13 AM

The 45.25 GB should be enough.


I would try the following:


1 - Boot into the Recovery volume (boot with the Command + R keys held down), select Disk Utility and run First Aid on the boot drive.


2 - reboot normally and run First Aid on the TM drive. This will take much longer than normal due to the complex ecosystem of file permissions and hard links.


If those fail to help and you don't have any files on the TM drive that are not on your boot drive you could erase the TM drive, reformat to APFS and start over with a fresh, full backup. Or get another external HD and start from scratch with it (if you have files on the current TM drive that are not on your boot drive and want to preserve them).

4 replies
Question marked as Top-ranking reply

Sep 20, 2021 10:13 AM in response to nrhbrussow

The 45.25 GB should be enough.


I would try the following:


1 - Boot into the Recovery volume (boot with the Command + R keys held down), select Disk Utility and run First Aid on the boot drive.


2 - reboot normally and run First Aid on the TM drive. This will take much longer than normal due to the complex ecosystem of file permissions and hard links.


If those fail to help and you don't have any files on the TM drive that are not on your boot drive you could erase the TM drive, reformat to APFS and start over with a fresh, full backup. Or get another external HD and start from scratch with it (if you have files on the current TM drive that are not on your boot drive and want to preserve them).

Sep 23, 2021 8:18 PM in response to Old Toad

With Apple Support's help, the problem was sort of resolved. Even though the TM dropdown from the menu bar consistently showed "Preparing Backup", a look into TM itself showed that there were actually several backups created. That being clarified, I went ahead with the updates. I have yet to run another backup since then. Thanks for your help.

What is wrong when preparing backup takes a long time?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.