Error 51 when copying or moving folders to external disks after macOS Tahoe on MacBook Pro

Hello everyone, after the update it gives me always error 51 while I try to move/copy folders to external disks I have always used. Anyone is having the same issue? How can it be solved? I can't move neither copy folders on external disks. I tried with 2 different disks and they give same error.


[Re-Titled by Moderator]

Original Title: Error 51 after updating to macOS Tahoe

MacBook Pro 14″, macOS 26.0

Posted on Sep 27, 2025 12:56 AM

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3 replies

Sep 27, 2025 5:14 AM in response to anila80

anila80 wrote:

Error 51 when copying or moving folders to external disks after macOS Tahoe on MacBook Pro

Hello everyone, after the update it gives me always error 51 while I try to move/copy folders to external disks I have always used. Anyone is having the same issue? How can it be solved? I can't move neither copy folders on external disks. I tried with 2 different disks and they give same error.

[Re-Titled by Moderator]
Original Title: Error 51 after updating to macOS Tahoe


?


is this <error 51> as written or more correctly error -51 (?) Maybe you can clarify that detail here.

Garbage in, garbage out



—what you do do not say is how these external disk are formatted?

please note: error code -50 paramErr = -50, /*error in user parameter list*/


—Also what are the file type you are trying to move contained in these folders, for added inforamtion in an effort to resolve your issue.



for macOS only files drives GUID/APFS


If proprietary software shipped on some drives (ex "Mac ready" or some such), I would turn to the vendor for some update to there software.


If this happens to be NTFS formatted drives— you would suspect updating your r/w third party software to be comparable....


some ex would be:


http://www.paragon-software.com/home/ntfs-mac/


http://www.tuxera.com/products/tuxera-ntfs-for-mac/


https://github.com/osxfuse/osxfuse/wiki/NTFS-3G


https://iboysoft.com/ntfs-for-mac/


https://macfuse.github.io/





—ref: Erase and reformat a storage device in Disk Utility on Mac

Erase and reformat a storage device in Disk Utility on Mac - Apple Support


Sep 27, 2025 5:45 AM in response to leroydouglas

Hi, thank you for your reply.


This is the error I have: "The operation can’t be completed because an unexpected error occurred (error code -51)"


The disks were used prior update and worked perfectly. Right after update stopped working on copy/past to disk from computer. They're ExFat formatted and been using them since I bought them without any issues.

Sep 27, 2025 5:59 AM in response to anila80

anila80 wrote:

Hi, thank you for your reply.

This is the error I have: "The operation can’t be completed because an unexpected error occurred (error code -51)"

The disks were used prior update and worked perfectly. Right after update stopped working on copy/past to disk from computer. They're ExFat formatted and been using them since I bought them without any issues.


re: < error -51 >


reference similar—

New Macbook Pro M4 won't recognize extern… - Apple Community


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Error 51 when copying or moving folders to external disks after macOS Tahoe on MacBook Pro

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