Issues copying TB of data from win pc to mac

Discussion in 'OS X Yosemite (10.10)' started by CavemanMike, May 31, 2015.

  1. CavemanMike macrumors regular

    Nov 8, 2013
    I have 1.75 TB of data on a windows 7 pc.

    Initially, I tried copying it over my wifi AC connection from the windows share to my macbook pro. It dies about 10% in with error -51 "unexpected error"

    Then I formatted a 2 TB drive as exFat (on the win7 pc) and used syncback to copy all the data on the D: to the external drive. Then I connected that drive (along with a 4TB WD raid drive) to my macbook and tried to copy the folder from one drive to the other. It died about 30% with an error: -43: "the operation can't be completed because on or more required items can't be found"

    Just for fun (and unrelated), I tried to copy my user profile to my NAS and that died in the middle.

    As a related question, I'm looking for some fancy utility where I could schedule backup jobs to backup a folder of local data to external and NAS volumes. Maybe if I had that, my initial copy of the 1.75 TB of data might have worked? Maybe MAC OS isn't great at copying large qty. of data?

    Thanks for any thoughts,
  2. cruisin macrumors 6502a


    Apr 1, 2014
    It sounds like something is buggy on your Mac. I managed to copy a 3 TB external drive to another external drive on my Mac, both running NTFS, and nothing went wrong.

    The WiFi copying issue (and the NAS issue) might be local interference, or something weirder. The USB drive issue is interesting, as a wired connection should work. Are you using an unpowered hub? It might be dropping the signal a bit under load (thus the message).

    I don't know of any utility that does this. Offhand, I would say use a Automator script, like this:

    All modern OS's can copy large files well. Its just that external issues, like a bad signal, can break something.
  3. Etan1000, May 31, 2015
    Last edited: May 31, 2015

    Etan1000 macrumors regular


    May 18, 2008

    Shouldn't you be using Windows Migration Assistant for this task?

    Windows Migration Assistant v1.0.5.7

    "This software will help you migrate data from a Windows PC running Windows XP, Windows Vista, Windows 7 or Windows 8. The Migration Assistant will launch automatically after it has been installed.

    For more information, please see "


    OS X Yosemite: Transfer your info from a PC

    Best wishes, Etan
  4. CavemanMike thread starter macrumors regular

    Nov 8, 2013
    Thanks everyone. Turns out it was AVAST antivirus that was fouling things up. I turned it off and the 1.7TB of data copied USB to USB perfectly!!! I will uninstall that and try SOPHOS instead.

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