Based on the provided information, the most likely cause is that the photos were stored in a OneDrive-synced location on the Mac and were deleted or removed while organizing folders. Recovery options depend on where the deletion occurred and whether OneDrive still has copies.
Use the following steps in order:
- Check OneDrive online
- Sign in to OneDrive in a browser (for a personal account or Microsoft 365 account) and look for the missing photo folders.
- If the photos are present, download them back to the Mac or let the OneDrive sync client re-sync them to a local folder.
- Check the OneDrive Recycle Bin
- In OneDrive on the web, open the Recycle Bin and look for the deleted photo files or folders.
- If found, select them and choose Restore so they return to their original OneDrive location.
- If using OneDrive for work or school, also check the second-stage recycle bin if available.
- Understand local deletion behavior
- If a OneDrive-synced folder (for example, a Pictures or Desktop folder that was inside the OneDrive folder) was deleted directly on the Mac, those items may have bypassed the local Trash and been deleted from OneDrive as well.
- If the files are not in OneDrive online or its Recycle Bin, there is no native Microsoft method to recover them; third‑party file recovery tools would be the only remaining option, and recovery is not guaranteed.
- If photos were in iCloud Photos or iCloud-synced folders
- If the photos were stored in an iCloud Photos–synced folder that was also visible in the Photos app on Windows or via OneDrive integration, deleting from that synced folder can also delete them from iCloud.
- In that case, use Apple’s recovery options (for example, Recently Deleted in Photos or iCloud’s recovery features) as described in Apple’s documentation linked from the Photos app article.
- Prevent future loss
- When using OneDrive on Mac, avoid deleting or moving the entire OneDrive root folder, as this can remove Desktop, Documents, Pictures, or other default folders that were redirected into OneDrive.
- Regularly verify that important folders are present in OneDrive on the web and consider enabling additional backup options as described in OneDrive backup documentation.
If the photos are not visible in OneDrive online, not in the OneDrive Recycle Bin, and not recoverable via iCloud/Apple tools, there is no built-in Microsoft recovery path; only third‑party file recovery utilities or backups (Time Machine, external backups) may help.
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