I am trying to copy text files to a thumb drive. They won't copy - I keep getting a message that I have to "authenticate" the thumb drive and I should click on "authenticate," but there is no such option anywhere. Sierra OS - Any ideas?
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Can't copy text files to external thumb drive
- Thread starter mlbroberts
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When you have to authenticate it means you do not ownership/permission to access, I would think bug from the lock down the OS trip Apple is on. Open the scary Terminal (located in the /Applications/Utilities/ folder) with the drive plugged in and type in then hit enter key ls -l /Volumes/ to check your permissions on the device.