7 Replies Latest reply: Sep 5, 2014 8:57 PM by mysticzzz
Matthew Knight Level 1 Level 1 (15 points)

I have just bought a 2TB external hard drive to replace my Time Machine 1TB external drive. Over the weekend, I have tried twice to copy the Time Machine data from my old drive to the new and on both occasions I have got this message:

 

"The finder cannot complete the operation because some of the data in “” can't be read or written. (Error code -36)"

 

Only about 25% of the data has been copied so far.

 

Any help would be much appreciated.


iMac, Mac OS X (10.6.8), 2.7GHz, Core i5, 4GB RAM
  • Matthew Knight Level 1 Level 1 (15 points)

    Having compared the two drives and what data has copied over, I can see the folder where the affected data is, but not sure how I can get around the problem.

     

    The folder is a user/library folder. I had tried deleting it but am told that I cannot modify back up data.

     

    Has anyone got any ideas how I can complete copying my Time Machine data from my old drive to my new drive?

  • WZZZ Level 6 Level 6 (12,775 points)
  • Matthew Knight Level 1 Level 1 (15 points)

    I've just seen a couple of suggestions of using Disc Utility to restore the data to the new drive, or using SuperDuper or Carbon Copy Cloner.

     

    Has anyone tried this before? Does it work?

  • WZZZ Level 6 Level 6 (12,775 points)

    I've called in the Time Machine cavalry to help.

  • Pondini Level 8 Level 8 (38,715 points)

    Matthew Knight wrote:

    . . .

    "The finder cannot complete the operation because some of the data in “” can't be read or written. (Error code -36)

    As indicated in the link WZZZ provided, error -36 is an I/O error, usually indicating a hardware problem.  If the data can't be read, you can't copy the backups.

     

    The main reason is, Time Machine backups are all linked together, sort of like a database, so if there's a problem in one spot, the whole thing is suspect (see the tan box in How Time Machine works its Magic for an explanation).

     

    Plus, the copy fails on the first error -- there may be more, perhaps many more, in the backup set. 

     

    There's a (smalll) chance the problem is a port or the cable; but if it failed at the same point both times, that's highly unlikely.  If not, you could try a different port and a new cable, but if these are your only backups, I'd recommend that only after you've got a backup on the new drive.

     

    The folder is a user/library folder. I had tried deleting it but am told that I cannot modify back up data.

    You can delete all backups of a particular folder, via the Time Machine interface, but because of the structure, that's probably going to fail, too. If you want to try it anyway, see Time Machine - Frequently Asked Question #12 (but see below first).

     

     

    I've just seen a couple of suggestions of using Disc Utility to restore the data to the new drive, or using SuperDuper or Carbon Copy Cloner.

    Also won't help in this case.  If the data can't be read, it can't be read.  This isn't a problem with the Finder (or Disk Utility or any other app) -- it's a problem either with the data on the disk, or the disk itself.

     

    You might be able to restore selected items, or even an entire backup, as long as you don't happen to hit the problem area, but it's entirely unpredictable.

     

     

    Worse, if the disk itself is failing, any attempts to read it may make it worse -- it might fail completely at any moment.

     

    So, your best bet is to keep the drive "on the shelf" and let Time Machine start fresh on the new drive ASAP, so you have a good backup of your current data.  If you need anything from the old backups, you may be able to see and restore from them, via the Browse... option, per Time Machine - Frequently Asked Question #17.  Again, it will depend on whether the disk is failing and whether you happen to encounter the problem area(s).

  • Matthew Knight Level 1 Level 1 (15 points)

    Thanks Pondini and WZZZ

     

    Yes, I am sure it is the same file that is causing the failure each time.

     

    I tried using SuperDuper last night to clone the old drive (this is before I saw your reply!) and got a bit more detail about which file it is. From what you say, it sounds like it would be a waste of time to try and remove the offending file from the backup.

     

    I will take your advice and start a fresh back up tonight, on my new drive.

  • mysticzzz Level 1 Level 1 (5 points)

    I am having this problem also. I am copying thousands of files at one time, backing up a calibre ebook database. With calibre, i have no control over filename structure, files are named by the program, and you may have 5 or 6 files for each book. It appears to be a filename structure incompatibility between NFTS external hard drives and Mac format drives. Not something i can manually repair. I bypassed the error by using oracles program virtual box, and installed windows xp. Then i used the copy program teracopy, running in Windows XP virtual box, to copy the files from the windows formatted external drive to my mac external drive. I have used teracopy for years in the windows environment, with good results. The only problem with this, is you need a copy of windows to virtualize, and you need a computer with enough power to run a vital copy of windows. It is a lot of work to set up, but it can help you overcome many incompatibilities when accessing info created on a windows computer. To find teracopy, just search google. Teracopy will go to the next file on a failure of coping one of the files in the copy list. Neither mac or windows built in copy software will do this. I have not found an equivalent to teracopy that will run on a mac os.