Time Machine backup on macOS Sequoia cannot be completed

I have the same problem, I removed the WDMyCloud drive from the Time Machine prefs, but, when re-adding it, the "Checking Capabilities of Time Machine backup drive" just hangs forever. Is there any other option?

I can mount and access the backup drive.

thanks.

I have the same problem. After removing the WD MyCloud Time machine drive, then re-adding it, I also got "checking capabilities of drive..." . Wouldn't add it. It would hang forever. Then I tried connecting with a different MyCloud server. It worked this time. .Was able to re-add the disk to TM.

thanks.

As I posted earlier, I was unable to successfully make a TM backup session after installing Sequoia. Today however, I was able to successfully back up after turning off the firewall on my MacBook. I then updated to 15.1 and successfully backed up with the firewall turned on. Can’t really explain this, but Time Machine now works properly.

I was seeing 'Back up Fail' and then I realised that after upgrading to Sequoia Time Machine had decided to remember an old TM disk which it couldn't find because I'd got rid of it - literally thrown it in the bin. The previous system software sensibly just worked with the disk that was actually connected and didn't try and find the old broken one. But Sequoia decided to make it complicated. So it turns out that backups were working fine but the message I was getting was that they'd failed. Once I deleted the old disk from TM settings it was fine.

Sequoia would not pick up my older hard drive from day one up updating to it.

I shelled out for a new DW Back up and set up Time Machine again from scratch. All working fine now.

The update must have screwed up my back up disc somehow? god only knows, it works now with the new one.

I have an M1 MacBook Pro running Sequoia 15.1.1 and it too could not complete the TM backup despite multiple attempts. I took the advice of an earlier reply and turned off the firewall before attempting another backup. With the firewall off TM backup went through with no problems. I don't have a need for auto backups and only do manual backups as needed so turning off the firewall, until Apple solves the problem, is not an issue for me.

"/etc/nsmb.conf" is not necessary. With "sudo sysctl debug.lowpri_throttle_enabled=0" alone, my Mac mini M2 needed 2 minutes for "preparing" and 3 minutes for backup and clean up (to Linux Samba server over LAN)!

Reference: https://mjtsai.com/blog/2016/03/16/massively-speed-up-time-machine-backups/

Update: Apple has since ghosted me for a second time despite having a customer service agent "dedicated" to my issue. Not the first for them....

Despite this, upgrading to MacOS 15.2 may have resolved? I'm not 100% sure at this point as I've had periods in the past where Time Machine has worked, only to stop days later. So far however, it has been about 5 days straight without errors.

After upgrading to 15.2 I did continue to get the errors, however I removed my two ssd's from Time Machine and I restarted my machine. I then re-added both drives and they continue to back up without issue, for now. Crossing my fingers.

Hi med8or,

I have this problem with Time Machine, at first I thought it was the external disk(s) I was using they were not to date (2 years old).

Now I have purchased a brand new branded external disk, this fault is exactly the same and with the two others sitting on the side, because the same thing happened when I copied folders and moved them from one disk to another.

I would have thought by now this would have been rectified especial with all the M4 Macs going out due to there release.

it has taken the edge of purchasing my new Mac mini, as backups are critical to me.

I just wish I read read this post sooner - it would have saved me £160.

When you do a Command I (Get Info) on the History.db file in /Users/your user account/Library/Safari/History.db do you see your User Account listed under Name and Privilege mine was missing when I went from Intel to M4 PRO I added it in and it solved my problem.

I have a Mac mini M2 running Sequoia 15.2. By switching OFF the Mac firewall then rebooting the Mac mini and then switching on the firewall again and adding Time Machine as a permitted app I can now back up to WD My Cloud EX2 Ultra using Time Machine via a 25 port LAN switch. Thank you to all who gave me advice, support and encouragement.

Pi-Jay,

Go into the /Users/your user account/Library/Safari you can get here by going to the Go Menu and holding down the Option Key Select Library. When you click on the History.db file press Command I to get the Information on the file make sure that your account is listed in the Sharing and Permissions section, you may need to add it in and set the Privilege Read and Write.

Note: You need to click on the Lock in the lower right hand corner before changing the Sharing & Permissions

Removing the Find My widget fixed the problem for me. Backups worked fine, then I added back the Find My widget and now I’m getting the error again after my iMac goes to sleep. We need a fix from Apple.

This was happening with me also. After looking at all of these comments, I was on the verge of purchasing a new backup drive. What I found worked for me was to reformat the backup drive, plug it into my 3 usb hub (instead of directly into the usb on the Mac Mini) and then set this drive up as the Time Machine backup drive. I have set it up to backup daily and for the last 3 days it is now working fine. I was previously under the impression that the Time Machine drive had to be plugged directly into the Mac. I guess now with Sequoia, it is best not to plug it directly into the Mac. As has been mentioned by many users, it was trying to do the backup but stop while the backup was in progress and eject the drive prematurely. I would get the warning that the drive was ejected improperly when Time Machine (or the system) was doing the improper ejecting of the drive. At least for now it is working properly. Or, at least I am getting backups. Hopefully, I won't have to test this any time soon.