How to restore files from a Synology NAS snapshot after accidental deletion or ransomware

Backup & Storage KB-804

Summary

This guide helps you troubleshoot and resolve: How to restore files from a Synology NAS snapshot after accidental deletion or ransomware. Follow the steps below to fix the issue.

Quick Tip: Need immediate assistance? 💻 Open a Ticket

Common Causes

Accidental deletion or ransomware encryption can be stressful, but if your Synology NAS is configured with snapshots, you can often recover individual files or folders quickly without performing a full system restore. This guide walks you through restoring files from a Synology snapshot using DSM.

Quick Fix Steps

Log in to DiskStation Manager (DSM).
Open Snapshot Replica from the DSM main menu.
Select the shared folder containing the missing files.
Select the snapshot taken before the deletion or encryption occurred.
Browse the snapshot, select your files, and click Restore.

Detailed Instructions

Prerequisites

Snapshot Replica package must be installed on your Synology NAS.
Snapshots must have been enabled for the shared folder before the data loss occurred.
You must have administrator access to DSM.

Step 1: Log in to DSM

Open your web browser and navigate to your Synology NAS IP address or QuickConnect ID. Sign in with an administrator account.

Step 2: Open Snapshot Replica

From the DSM desktop, click the main menu and open Snapshot Replica.

Step 3: Select the affected shared folder

In Snapshot Replica, select the shared folder where the deleted or encrypted files were stored from the list of protected folders.

Step 4: Select the correct snapshot

A list of available snapshots will appear, sorted by date and time. Choose a snapshot created before the files were deleted or encrypted. Click Browse to view the contents of that snapshot.

Step 5: Restore your files

Inside the snapshot view, navigate to the file or folder you need to recover.
Select the item(s) you want to restore.
Click Restore.
Choose whether to restore to the original location or a different folder.
Confirm the restore operation.

Restoring to a different location is safer if you suspect ransomware. This prevents overwriting any remaining recoverable data on the NAS.

Troubleshooting

No snapshots are listed

If no snapshots appear, snapshot scheduling was not enabled for that shared folder prior to the data loss. In this case, recovery via snapshot is not possible. You may need to check external backups or contact Open a Ticket for further assistance.

The Snapshot Replica package is not installed

Go to Package Center, search for Snapshot Replica, and install it. Then return to Snapshot Replica and try again.

Restore fails or files appear encrypted

If you suspect ransomware, disconnect the NAS from the network immediately to prevent the infection from spreading to backups or other devices. Do not restore files until the threat has been contained.

If restored files are still encrypted, the snapshot itself may have been affected. Try selecting an earlier snapshot. If all snapshots are encrypted, you will need to rely on off-site or offline backups.

Permission errors during restore

Ensure you are logged in with an administrator account. Standard user accounts may not have permission to restore files to their original location.

For help configuring snapshot schedules or setting up off-site backups to protect against future data loss, Open a Ticket.

You may also find our guide on How to backup photos to external drive useful for creating additional local copies of important data.

Still Having Issues?

Need more help? If the issue persists after trying these steps, please open a support ticket and our team will assist you.

💻 Open a Ticket