Warning: file opened from server backup copy and not saved to storage in Nextcloud integration

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1

Hello,

After updating Nextcloud and testing ONLYOFFICE with public shared links, I opened one specific XLSX file and ONLYOFFICE showed this warning:

“This file is opened from a server backup copy and is not saved to storage. Use the ‘Save as…’ option to save it to a drive.”

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This happened only with one specific file. Other XLSX files opened through public links did not show this warning.

Context:

  • Nextcloud: 32.0.11
  • ONLYOFFICE Document Server: 9.4.0.1
  • Deployment: Docker / Portainer
  • Nextcloud integration with ONLYOFFICE connector
  • Public shared link editing
  • Autosave enabled
  • Fast co-editing mode
  • ForceSave is now enabled

Questions:

  1. What exactly does this warning mean in the Nextcloud integration?
  2. Why would ONLYOFFICE open a file from a “server backup copy” instead of the normal Nextcloud storage file?
  3. Can this happen if the file was open during Nextcloud maintenance mode or redeploy?
  4. Where is this backup copy stored on the Document Server?
  5. Is there a safe way to force ONLYOFFICE to save that backup copy back to Nextcloud?
  6. Could opening/saving this backup copy affect formulas or formatting in an XLSX file?
  7. How should admins safely recover from this situation?

In my case, renaming the file seemed to stop the warning from appearing, but I would like to understand the correct procedure and whether there is any risk of data/formula/formatting loss.

Thank you.

2

Hi @jcordeirom20-cmd,

This warning means that Document Server previously tried to save the file back to Nextcloud but the callback failed — most likely because Nextcloud was temporarily unreachable during the update. When that happens, Document Server keeps the unsaved version in its internal “forgotten” directory.

When you opened the file and saw this warning, you were already working with that forgotten backup. The warning disappeared not because of the rename — renaming does not change the document key in Nextcloud. It most likely resolved itself when you opened and closed the file, which triggers Document Server to retry saving it back to Nextcloud.
It affected only one file because that was the only one with an active editing session at the moment the callback failed.

As a preventive measure for future Nextcloud updates, you can use the prepare4shutdown command on Document Server before starting the update — this gracefully finishes all active editing sessions and avoids this situation.

More details on how saving works:
https://api.onlyoffice.com/docs/docs-api/get-started/how-it-works/saving-file/