I have constant problems moving large files in Mountain Lion. When I say large I would say roughly 2GB or larger, which means nearly every iso and vmdk I touch. This can occur moving a file to or from a USB disk, a FW800 disk, a samba share, a netatalk share.

For instance, here is the latest error: "The Finder can't complete the operation because some data in "Fedora-18-x86_64-DVD.iso" can't be read or written. (Error code -36)"

I know the data is not corrupt because I can use rsync to copy this file to the exact same destination and it will succeed, just that finder will fail to copy it. I've also used the same file to install a vm which worked fine as well as moved the file with a USB stick which for no apparent reason succeeded. On top of that when I share out files using SMB from the same Mac and try to move the file from a windows server the connection will hang up halfway through the copy for no apparent reason. Is anyone aware of a larger bug or problem with large files in 10.8?

  • 1
    Same problem when copying from Mountain Lion Server share point using SMB. The copy will stop mid way. Copying to the server is fine. Also if Outlook opens a .pst file on the server Outlook freezes randomly I suspect its the same issue.
    – user40314
    Jan 24, 2013 at 19:53
  • Check the integrity of your hardrive (don't rely on Disk Utility). It smells like bad cells on a failing drive to me.
    – user10355
    Jan 24, 2013 at 21:24
  • I have this problem too. Nightmare.. Two months on - any news from Apple?
    – user45191
    Mar 15, 2013 at 6:05
  • This error is usually indicative of hard drive problems (bad sectors). RSYNC won't have a problem because it copies the corrupt sectors (like cloning software). I would run a thorough test before assuming it's a software issue. In my case, I had these on a drive that would eventually fail (as reported by SMART and if SMART catches it, you know it's bad). You should verify the state of your HDD.
    – user10355
    Mar 15, 2013 at 6:29
  • I came across similar issue when tried to copy my huge 50G .dmg file. The finder fails each time. Then I used unix command "cp" and it worked. Similar issue was in Lion ... I have no idea why Apple can not fix this issue.
    – user56942
    Sep 12, 2013 at 3:52

1 Answer 1


We had the same problem. Communication stops briefly on extended transfers of any kind.

I contacted Apple Senior support who were actually able to reproduce the problem. I was told that Apple will release an update after they solve the issue.

Obviously until then we all must wait.

  • Maybe that's the 10.8.3 everyone is excited about. The fact that apple abandoned the Samba project makes me want to move to Fedora for good. The last thing I want apple deciding for me is what I can do with Windows file shares. Feb 1, 2013 at 18:01

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .