7 Replies Latest reply: Nov 26, 2012 9:53 PM by Jon Hermansen
Joey!! 【ツ】 Level 2 (255 points)

I am backing up my rMBP running 10.8.2 to a third gen Time Capsule over Wifi. It has been backing up successfully since I bought it a few months ago. It stopped backing up for 12 days (because I was away from home, so this is expected). During that time I updated to the latest notebook update (MacBook Air and MacBook Pro Update 2.0), which changed the build number to 12C3006. The next time it tried to back up, it performed a deep scan, and stated it had to back up around 8 GB (expected because of the new update). It backed up, but when it was almost completed, I got this message:

"Time Machine completed a verification of your backups on "TC". To improve reliability, Time Machine must complete a new backup for you."

Screen Shot 2012-11-16 at 2.02.47 PM.png

My questions are: Is there a way to figure out what caused this to occur? Is there a way to fix it, or do I have to start a new backup and wipe out all of my backup history? How can I prevent this from occurring in the future?


Thank you!

MacBook Pro (Retina, Mid 2012)
  • LaPastenague Level 8 (48,834 points)
  • Joey!! 【ツ】 Level 2 (255 points)

    Thank you, I figured the great Pondini would have good information about this message!


    Unfortunately, it doesn't provide any insight as to what caused it, nor really how you can prevent it from occuring in the future. I guess I have to start over and just hope it works. And really hope it isn't a problem with the Time Capsule. It has been working great for my iMac, which has been backing up for nearly a full year to the same TC and never encountered this issue, and it is still working great after receiving this error on the rMBP.



  • LaPastenague Level 8 (48,834 points)

    As pondini says.. the causes are many and various.. but basically it has corrupted itself.. remember TM is always meant as a current snapshot of the computer.. if you want longer term storage you should use a disk image.


    Wireless is definitely part of the trouble.. more packets are corrupted and sometimes missed I guess.. then TM checks the backup it discovers the corruption but instead of fixing it just starts all over again.


    We do recommend to people if possible use ethernet.. but for laptop users that isn't easy.


    Also it is the setup of the TC in the network.. if you have the TC setup in bridge or as a router that is fine. But if you are trying to transfer packets by double hop wireless that is to be avoided.


    I would also just because Mountain Lion is a bit more difficult on the networking.


    Reset the TC and use all SMB type names.. short, no spaces pure alphanumeric.

    That is for TC itself, wireless.. I recommend different names for 5ghz so you can force connection and the hard disk name.


    Fix and lock wireless as well. All of it can help.. a bit.

  • Joey!! 【ツ】 Level 2 (255 points)

    Well, I don't think anything could be causing it that I'm aware of. Interference, power source, nothing I can think of. I've been backing up my iMac to the same TC wirelessly since December 2011 (and still am) and have never encountered this problem.


    In any case, I went ahead and started a new backup. It took a couple hours to back it up over Wifi, and there were no hiccups. Just sad I lost all backup history, but oh well. I still have my iMac backup history clear to last year.

  • LaPastenague Level 8 (48,834 points)

    If you want to keep the history.. then archive off the TC to USB drive.


    The only trouble is apple left that function out of the new airport utility, so you have to use v5.

  • Joey!! 【ツ】 Level 2 (255 points)

    That wouldn't be possible - that was way too many GB for a USB drive. It wasn't super important because I still have my iMac backup history, which was basically the exact same as the rMBP because I restored my data via Time Machine from my iMac to my rMBP when I bought it.

  • Jon Hermansen Level 1 (0 points)

    I'm having the same issue, Mid-2012 rMBP and a 3rd Gen Time Capsule. Everything is up to date. I have an apostrophe in my Computer Name and have never had an issue with that.


    I'm just trying to figure out how I can modify the .sparsebundle file so I can start a new backup without losing my history. I already figured out how to manually mount and copy files out of the sparsebundle, so not having it as my main backup "file" would be perfect.


    If anyone knows how, feel free to post it here. If I figure it out, I'll do the same