Why Does Backup to Thumb Drive Fail?

New Mac user here …

When I try to back up to a thumb drive, I get this message:

A backup could not be created at ‘/Volumes/SCRIVBACKUP/The Abducted Heiress 2018-07-31 08-48.zip’.

Can anyone tell me why?


Are you able to create the backup elsewhere and then drag it to the thumb drive in Finder? Can you backup to a different thumb drive?

Thumb drives are generally slower and less reliable than, say, your local disk. So it could be that an operation is timing out or that a write attempt is failing too often. Or the drive could just be full.


I think I figured it out. I formatted another thumb drive using the Mac OS format, and I was able to back up to that drive, so I guess I need to reformat the other thumb drive.

I back up and save Scriv projects to a thumb drive all the time and use the same ones I use on my Windows machines. However, my MacBook Pro is a late 2013 model, and since yours is a new machine, I wonder if it has to do with all this USB-C stuff – that’s from memory, latest and greatest USB incarnation anyway.

Glad you found a way to make it work.

It depends upon which file system is chosen, and there’s special handling or third party software required to enable write privileges to NTSF for Mac. One of the FAT options is safer for cross compatibility. Decent article here as to the difference:
osxdaily.com/2012/04/22/format-d … ompatible/

(The article predates APFS’ release, but that’s not relevant to this issue.)

Yes, I’ve formatted to FAT now, and it works fine (and will be restorable on a PC.