Mojave time machine back up failing

I just simply chose, "clean install aka reinstall" instead of "Restore from time machine backup" without wiping the drive using disc utility. Just don't wipe your drive, thats all. Just follow every step, minus the part about wiping your hdd or ssd. 😀 Basically, it is just a re-update. It leaves all your personal files in tact, but it can fix system files that may not have copied over correctly the last time you updated. It is not a true clean install, but if your download was corrupt or the install of that downloaded file was not installed correctly (one line of code is all it takes) then you could easily have problems like you are having. A "re-update" has saved a few mac installs already for me. including my girlfriends macbook pro mid 2012 model.

This matches my experience. The HDD in the Time Capsule is formatted as case sensitive. When I formatted my external Thunderbolt HDD as Mac OS Extended (Case-sensitive, Journaled) it worked too. Be aware that there are others reporting issues about Time Machine running out of space even with the reformatted external drive, but the reformatted drive workaround worked for me and I've seen no subsequent errors. I also verified with a second external drive that the SuperDuper! backup program works perfectly well with Mac OS Extended (Case-sensitive, Journaled) so I am confident that I have a reliable backup system in place until Apple figures out what is going on. There is absolutely no downside of formatting a disk that is dedicated for backup use with Mac OS Extended (Case-sensitive, Journaled). You can leave it that way forever regardless of Apple's eventual fix.

I also did not have App Cleaner & Uninstaller installed. If a misbehaved app is able to break Time Machine this could turn into a whack-a-mole situation.

Did you read the posts about the App Cleaner related problem? Several folks have fixed this issue by addressing the App Cleaner issue. I did not have App Cleaner installed but the case sensitive reformat of my backup disk fixed my problem, as did backing up to a Time Capsule (which is formatted case sensitive). If neither the App Cleaner workaround nor the case sensitive format of your backup disk workaround alleviate the issue there is likely another failure mode that is causing the problem with Time Machine. I tried working with Apple on this for well over a week but their diagnostic data capture process would not work with my online connection and they gave up without resolving the problem. From my perspective they do not appear to be very interested in finding the root cause of this problem but I hope that I am wrong. A misbehaving app should not be allowed to break Time Machine.

You have to do the same work as I did to find out which file is responsible on your machine:

Exclude everything from the root of your harddisc.

See if TM works now.

Then remove one directory by one from the exclusion list and everytime do a TM backup.

When TM fails, you have found the directory below which the "bad file" must be.

Then go into this directory and exclude everything.

Then remove one directory by one from the exclusion list and everytime do a TM backup.

When TM fails, you have found the subdirectory below which the "bad file" must be.

And so on....

It will probably take a few hours to find the "bad file(s)".

Please document here which one it was!

I contributed to this apparently endless string of posts about Time Machine failing in Mojave some time ago. Since then much of the discussion has been well outside my technical competence, but one very useful contribution pointed out that Time Machine is designed to give way to any other data-transferring or -copying applications that may be running.

I use Sync Folders Pro, running all the time, to copy the contents of my Desktop and Documents folders and a folder containing the scores of my musical compositions to my iCloud folder; I also use Carbon Copy Cloner as a backup system in parallel with Time Machine (belts and braces!). After updating to Mojave, I experienced the problem of TM not completing its backup that has been the subject of this string, and therefore abandoned TM for a while; then tried to do a Time Machine backup, but first shut Sync Folders Pro down and ensured that CCC was also not running. The TM backup still did not complete.

Last night I tried TM yet again, having not used it for probably 2 or 3 months, but I first shut down every and all applications that I have set up to start when I start up the computer. TM remained on 'Preparing Backup' for over 3 hours — even though I have a modest hard drive of a mere 479.89 GB capacity — and I feared the worst, but then it started to back up and completely finished the backup in another 2 hours or thereabouts.

So this might be the generally-applicable and technically simple answer to the TM problem: shut down every single running application apart from Time Machine when performing a TM backup.

I found that reformatting the drive with Journaled- case sensitive, as was suggested in a previous reply, solved my problem

Hummmm... I just tried to install again "App Cleaner & Uninstaller", then run a new TM backup.

TM complete without error...

So, this is not ONLY the "?" in the path that caused the problem. I think the problem is because of 2 folders with "similar names" :

1) App Cleaner & Uninstaller

2) App Cleaner & Uninstal?ler

I believe TM was screwed up with those two folders and their names.

So for those who use "App Cleaner & Uninstaller", I recommend to completely uninstall this software (ie: In app folder and in ~/Library/Containers/com.nektony.App-Cleaner and then install this software again.

In my case, this solved issue with TM.

Thanks to this thread, I fixed my problem. I excluded the App-Cleaner files from my library/containers folder and reformatted the external hard drive to Mac OS Extended (Case-sensitive, Journaled).

Now life is good.

However I am ****** that AppleCare support didn't return my 6 VM nor several EM over the weekend.

🙂

I got my full backup!! Format on the external HD extended case sensitive and just excluded App Cleaner and Uninstaller. Hats off to all the third party vendors trying to keep up with all the changes. IT'S NOT EASY. Love the app!!

I had similar issues. I attached a second drive to perform the backup just in case my standard time machine raid drive was broken.

Repaired also the rights on the source drive with the recovery partition etc.

By coincidence I opened then the Time Machine in the preferences and unlocked the settings as admin.

Then the backups on all drives worked as usual.

I think all finding are related to the Apple SIP (Integrity Protecion) which was again improved in Mojave.

This is also reflected in the Konsole when you go through the crash and problem system messages.

Please try yourself and keep us posted.

It's been awhile since I visited this thread, but I turned on automatic backups a couple weeks ago and haven't had any issues. That was after initiating the backups manually every few days and having them complete without issues.

One thing I did prior to going back to automatic backups: I removed a very large disk image file that was in a folder that was being backed up via Time Machine as well as to my iCloud Drive. The latter is actually what caused me to investigate further, as my network would slow to a crawl whenever my iMac or my Mac mini uploaded or downloaded the file.

Offloaded the file and no more slow downs and Time Machine works again (so far).

I switched to MacOS Extended Journaled Case Sensitive and it worked! Time Machine was able to make a successful first backup.

I would recommend switching your Drives to that if you can.

Was having the exact same issues as everyone else. Nothing worked until...I turned off an outgoing firewall. Now Time Machine works. Hope something similar may help you.

scotsman

I have got the same problem. Seems like App Cleaner has an issue with mojave and the backup with Time Machine.
I removed App Cleaner and after that Back up worked without any issue.