When I copy files from macOS X to a USB external hard drive disk with both command or drag and drop action, the operation can not be processed. After some time investigate with google, I finally found the reason. This article will tell you how to resolve can not copy files from macOS to USB external hard drive disk issue.
1. Format The USB Disk With ExFat File Format.
The main reason for this issue is macOS can only read NTFS format files but can not write files to NTFS disk. So if the USB disk is NTFS format, then the copy and paste operation can not be operated. So we should change the USB Disk file format to others such as FAT or ExFAT. And ExFat is a more good choice.
1.1 Change USB Disk File Format Steps.
- Open macOS Finder —> Applications —> Utilities —> Disk Utility.
- Select the USB disk in the left panel.
- Then click the Erase button at the top of the right panel. Select ExFAT in the Format drop-down list and begin to format.
- After the format process complete successfully, you can copy files from macOS to USB disk successfully.
2. How To Copy Files From macOS To USB External Hard Drive In Command-Line.
- Open a terminal and run the command
cp -R Documents /usb.
-Rparameter will copy all the subdirectories under the
Documentsdirectory to the USB external hard drive.
- But above command may raise an error message such as
usb/Pics: No such file or directory.
- This is because the USB external hard drive is mounted under
/Volumesfolder, so you should add the
/Volumesdirectory before USB disk name when you run the cp command.
cp -R Documents /Volumes/usb-name