30K+ photo mysteriously gone from OneDrive during mobile transfer

Hello Jab Buggakupta,

I understand that you are having issue with recovering missing OneDrive photos. I truly understand how you feel. Let me assist you go through this situation.

According to my own research, when Samsung Gallery is linked to OneDrive, any bulk deletion initiated by the device or gallery app is treated by OneDrive as a real user action and syncs back to the cloud. OneDrive then sends a “large number of files were deleted” alert email exactly what your mom received. OneDrive cannot distinguish accidental device‑side deletions from intentional ones. For more information, please check at this page: https://support.microsoft.com/en-us/office/restore-deleted-files-or-folders-in-onedrive-949ada80-0026-4db3-a953-c99083e6a84f

Turning OneDrive Sync OFF after the process starts does not stop deletions that already queued during the transfer. Here is my suggestion for you:

1. OneDrive Recycle Bin

Deleted OneDrive files are kept in the Recycle Bin for 30 days on personal accounts. If they are still there, they are fully recoverable.

• Sign in to OneDrive on the web (not the app): https://onedrive.live.com/login
• Select Recycle bin (left side)
• Look for: Large photo folders Mass deletions with the same timestamp
• Select the items and choose Restore

If the Recycle Bin was emptied or overflowed, those files are permanently deleted from OneDrive storage.

2. “Restore your OneDrive” (30‑day rollback)

If your mom has Microsoft 365, OneDrive allows rolling back everything to a previous point in time (before the deletion). This undoes bulk deletions.

• Go to OneDrive (web)
• Select Settings > Options
• Choose Restore your OneDrive
• Select a date before the phone transfer
• Review the activity chart and restore

Please note this information:

• Works only for actions within the last 30 days
• Albums are not restored
• If files were already permanently deleted from the Recycle Bin, they cannot be recovered

You mentioned this already failed so the files might no longer present in OneDrive’s retention window.
3. Check Personal Vault

Photos stored in Personal Vault do NOT appear in search results and can look “gone” unless explicitly shown.

• Open Recycle bin
• Select Show Personal Vault items
• Unlock the vault and check contents

4. Check the OLD Samsung phone

Do not power on or reset the old phone repeatedly. Turn on Airplane mode.

Check:

• Samsung Gallery
• DCIM folder via file manager
• Secure Folder (if used)

If photos exist locally, copy them to a PC first before reconnecting OneDrive.

I hope this will help with your situation. Please feel free to reach back if you have further update or more questions.

Best Regards,

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