Cannot copy file from external HD to external HD because 'item already exists'.

[schenz]

Hi all,

I am trying to copy a large file (a Photos library of 135 GB) from one external HD to another external HD (both connected to my Mac via USB). The target HD is newly bought and freshly formatted (Mac OS Extended Journaled). When copying the file, the transfer proceeds until about 60 GB in, then an error message appears:

The operation cannot be completed because an item with the name "<insertfilenamehere>" already exists.

… which is obviously not true. In any case, the transfer is cancelled and the file is not copied to the target HD.

• I have tried a few times and always get the same result (and yes, I deleted any files on the target HD and emptied the trash bin between trials).
• I have copied other files between the same two external HDs successfully. Of course, these other files all have names different from the one file that doesn't work. However, these files are all smaller than 100 GB.

I am looking forward to hearing your ideas!

Daniel


Relevant (?) system configuration:

• Mac mini (2018)
• macOS 10.15.5
• Source HD: ASMT 2105 (Mac OS Extended Journaled) (*)
• Target HD: I-O Data HDCZ-UT (Mac OS Extended Journaled)

(*) This used to be the internal HD of one of my old Macs, which I scavenged and use as an external HD via a SATA-to-USB case. Recently, this HD has run into problems, something along the lines: 'The disk cannot be repaired. It cannot be modified but it can be read, so please copy all your data to a different disk.' So I bought a new HD and tried to copy all files, and that's where the problem I'm describing above occurs.

 

[schenz]

I solved the problem and am posting the solution here for reference to anyone who might have a similar issue.

For some reason, the drag-and-drop copy doesn't work, but using the command line in Terminal works just fine. So I just typed this command into Terminal:

cp -R /Volumes/Source/File.extension /Volumes/Target/

and, after quite a while of hidden copying, I had my copy where I wanted it to be. I still don't know what the problem was, but now I have a solution.

For anyone interested, the '-R' portion is there because the file I wanted to copy turned out to actually be a directory ('folder'), so I needed to add this 'recursive flag' to make the computer copy the folder and all its contents.

The lesson here is that it is worth learning basic common line commands, because they are more powerful even for very basic things.

LLAP