External drives · Mounting and drive problems
How do I stop "Disk Not Ejected Properly" warnings every time my Mac sleeps?
Short answer: Something is cutting power to the drive while the Mac sleeps — usually a hub or dock. Plug the drive directly into the Mac, use a good cable, and on a desktop turn off hard-disk sleep in Energy settings if your drive struggles to wake.
When the warning appears after every sleep, the connection is being cut while the Mac sleeps — usually by a hub, dock or adapter that powers down its ports, or by a bus-powered drive that can't wake reliably. Connecting the drive straight to a port on the Mac fixes it in most cases.
Try, in order:
- Plug the drive directly into the Mac instead of through a hub or dock.
- Use the cable that came with the drive, or another known-good one.
- If you must use a dock, use one with its own power supply.
- On a desktop Mac, check System Settings → Energy (or Energy Saver) for an option to put hard disks to sleep, and turn it off if your drive struggles to wake.
If the drive still drops out, test it with First Aid and on another port — an intermittent drive is worth replacing before it fails. Storage Studio pauses its moves while the drive is away and carries on when it returns.