Is it a Virus?
✔ NO - Safe
Must be in C:\Windows\System32\drivers\volsnap.sys
Warning
Shadow Copy operations involve multiple components
VSS writers and snapshot requests may cause volsnap.sys activity
Can I Disable?
✖ NO
Volsnap.sys is a core OS driver required by the Volume Shadow Copy Service; disabling may break backups and restore points
What is volsnap.sys?
volsnap.sys is the Windows kernel-mode driver behind the Volume Shadow Copy Service (VSS). It coordinates snapshot creation for backups, restore points, and file history by interacting with writers, providers, and the OS to capture consistent data copies even when files are in use.
volsnap.sys is a kernel-level driver that coordinates VSS operations, enabling safe snapshot creation by synchronizing writers, providers, and disk activity. It runs in kernel space to capture state without stopping applications, typically during backups.
Quick Fact: VSS shadow copies first gained prominence with Windows Server backups; volsnap.sys ensures consistency across mounted volumes during those operations.
Types of volsnap.sys Operations
- Shadow Copy Ready: Prepares a snapshot so backups can proceed without interrupting user activity
- Snapshot Creation: Coordinates streams to produce a point-in-time copy of a volume
- Snapshot Commitment: Finalizes and stores the shadow copy metadata for restore points
Is volsnap.sys Safe?
Yes, volsnap.sys is safe as a legitimate Microsoft kernel driver loaded with Windows.
Is volsnap.sys a Virus or Malware?
The real volsnap.sys is a system driver from Microsoft. Malware can masquerade with similar names, so verify the path and digital signature.
How to Tell if volsnap.sys is Legitimate or Malware
- File Location: Must be in
C:\Windows\System32\drivers\volsnap.sys. Any volsnap.sys outside this folder is suspicious.
- Digital Signature: Right-click the file in Explorer → Properties → Digital Signatures. Should show a signature from Microsoft Corporation.
- Resource Usage: Normal operation shows low CPU and modest memory usage. Sudden spikes when idle may indicate issues.
- Behavior: Volsnap.sys should not spawn new processes or act as a userland service; it operates as a kernel driver.
Red Flags: If volsnap.sys is located outside C:\Windows\System32\drivers, lacks a valid signature, or triggers frequent VSS errors and crashes, scan for malware and verify OS integrity with built-in tools.
Why Is volsnap.sys Running on My PC?
volsnap.sys runs as part of the Volume Shadow Copy Service to enable backups, restore points, and file history. It may activate during backup windows, OS maintenance, or when a shadow copy is requested.
Reasons it's running:
- Active Shadow Copy Requests: Backup software or system tasks request snapshots, causing volsnap.sys to engage.
- System Restore or File History: Windows features that preserve previous file versions use VSS, triggering volsnap.sys.
- Backup Scheduling: Regularly scheduled backups (including cloud or enterprise backups) invoke VSS consistently.
- OS Maintenance windows: Windows maintenance tasks may run VSS components to checkpoint disk states.
- Startup and Background Services: VSS-related services initialize on boot or run in background to support restore capabilities.
Can I Disable or Remove volsnap.sys?
No, you should not disable volsnap.sys. It is a core OS driver required by the Volume Shadow Copy Service for backups and restore points.
How to Stop volsnap.sys
- Stop VSS-Related Services: Open Services (services.msc) and stop the Volume Shadow Copy service, then set Startup type to Manual or Disabled (not recommended on production systems).
- Disable Shadow Copy UI: In System Properties or Group Policy, disable Shadow Copies if you understand backup implications.
- Re-evaluate Backup Software: If backups are causing issues, adjust backup windows or settings to minimize VSS contention.
- Reboot: A full reboot may be required after stopping services to ensure a clean state.
- Monitor for Errors: Check Event Viewer under Windows Logs > Application and System for VSS-related errors.
How to Uninstall volsnap.sys
- ✔ Windows features cannot remove volsnap.sys directly; it is part of the OS.
- ✔ To limit shadow copies, modify VSS settings and disable shadow copies for specific volumes via vssadmin or Group Policy.
- ✔ Consider OS repair or reinstallation if volsnap.sys is corrupted.
Common Problems: Shadow Copy Failures and VSS Errors
If volsnap.sys is involved in backup or shadow copy issues, use these common causes and solutions to restore stable operation.
Common Causes & Solutions
- Insufficient disk space for shadow copies: Free up space on the target volume, or configure backups to use a larger destination with adequate space.
- Corrupted VSS writers: Open an elevated command prompt and run: vssadmin list writers; restart the Volume Shadow Copy service and retry backups.
- Conflicting backup software: Update or temporarily disable third-party backup tools that may conflict with the native VSS provider.
- Outdated Windows components: Install the latest Windows updates to ensure VSS components are current.
- Volume in use or file system errors: Run chkdsk /f on the affected volume and ensure files in use are properly handled during snapshot operations.
- Improper permissions: Ensure the VSS service and backup software have the required administrative privileges.
Quick Fixes:
1. Open an elevated CMD and run: vssadmin list writers to identify issues
2. Free disk space on volumes involved in shadow copies
3. Restart Volume Shadow Copy service (services.msc) and retry backups
4. Update Windows and installed backup software
5. Check Event Viewer for VSS-related errors and address underlying causes
Frequently Asked Questions
What is volsnap-sys?
volsnap.sys is the Windows Volume Shadow Copy Service driver that coordinates snapshots for backups, restore points, and file history.
Is volsnap-sys safe on Windows?
Yes, volsnap.sys is a legitimate Microsoft kernel driver. Verify path (C:\Windows\System32\drivers\volsnap.sys) and digital signatures to confirm authenticity.
Can volsnap-sys cause high CPU or disk usage?
During shadow copy operations or heavy backups, there may be increased disk I/O and minor CPU activity. Prolonged high usage warrants checking for backups or faulty writers.
How do I check volsnap.sys location and signature?
Navigate to C:\Windows\System32\drivers\volsnap.sys, right-click, Properties, Digital Signatures; verify Microsoft Corporation as the signer.
What happens if I disable volsnap.sys or the VSS service?
Disabling can break backups and system restore. Only change VSS settings if you understand backup implications and have alternative restore plans.
How do I fix VSS errors caused by volsnap.sys?
Check writer status with vssadmin list writers, restart the VSS service, ensure disk space, apply latest Windows updates, and review Event Viewer for detailed error messages.