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Troubleshooting

Why External Storage Cannot Be Written To

Check the drive in Files first, then reselect the folder in Watermelon Backup and try a small backup again.

Updated July 17, 2026

Check it in Files

  • Open the iOS Files app.
  • Open the external drive or Files provider you selected.
  • Try creating a folder or small test file in the target location.
  • If Files cannot write there, Watermelon Backup cannot write there either.
  • If the drive format looks wrong, check Apple's external storage guidance for iPhone.

Reconnect the Node

  • Reconnect the drive or reopen the Files provider.
  • In Watermelon Backup, add or reselect the External Storage Node.
  • Choose a folder that is writable in Files.
  • Return to Home and wait for the Node to become available.

Try the backup again

  • Select one small local-side month first.
  • Tap Execute and confirm Backup.
  • Keep the drive connected until the task and manifest write finish.
  • If it still fails, export the diagnostic log and contact us.

Download Watermelon Backup

Install Watermelon Backup from the App Store to follow this guide on iPhone.

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