VSS Command Line Repairs

Overview

The Volume Shadow Copy Service (VSS) is a critical Windows component that NovaBACKUP relies on to create consistent backups of your system. When VSS becomes corrupted or unstable, it can cause backup failures, incomplete shadow copies, or service errors. This guide provides command-line procedures to repair and reset VSS and related COM components.

⚠️ WARNINGS & IMPORTANT NOTES

Advanced Users Only: This guide is intended for users with working knowledge of command prompts and Windows system administration.
Administrator Rights Required: All commands must be run with full administrative privileges.
Expected Failures: Some commands may fail—this is normal and acceptable. If a command fails, verify you typed it correctly and proceed with the remaining commands.
Service Dependencies: If you have SQL Server, Exchange, or other applications using VSS writers, you may want to stop those services first to avoid conflicts.
Backup Your System: Consider creating a system backup before performing these repairs, particularly if your system is experiencing frequent crashes.

Before You Begin: Prerequisites

Close NovaBACKUP completely (including system tray)
Stop dependent services (if applicable):
- SQL Server VSS Writer
- Exchange VSS Writer
- Any third-party backup applications
Open Command Prompt as Administrator:
- Windows 10/11: Right-click Command Prompt or PowerShell and select "Run as administrator"
- Windows Server 2016/2019/2022: Right-click Command Prompt and select "Run as administrator"

VSS Repair Instructions by Operating System

Windows 10 | 11 & Server 2016 | 2019 | 2022 (Recommended)

These instructions use the most current VSS repair approach.

Step 1: Navigate to System32

cd %WINDIR%\System32

Step 2: Run VSS Service Repair Commands (copy and paste all at once):

net stop VSS
net stop swprv
regsvr32.exe /s ole32.dll
regsvr32.exe /s oleaut32.dll
regsvr32.exe /s comcat.dll
regsvr32.exe /s vssapi.dll
regsvr32.exe /s es.dll
regsvr32.exe /s stdole2.tlb
regsvr32.exe /s mscoree.dll
regsvr32.exe /s vsmgmt.dll
net start swprv
net start VSS

Step 3: Clear Shadow Copies

vssadmin delete shadows /all /quiet

Step 4: Verify VSS Writers

vssadmin list writers

Step 5: Close Command Prompt and Reboot

exit

Then restart your computer.

Windows 8 | Server 2012 / 2012 R2

Step 1: Navigate to System32

cd %WINDIR%\System32

Step 2: Run VSS Service Repair Commands (copy and paste all at once):

net stop VSS
net stop swprv
regsvr32.exe /s ole32.dll
regsvr32.exe /s oleaut32.dll
regsvr32.exe /s comcat.dll
regsvr32.exe /s vssapi.dll
regsvr32.exe /s es.dll
regsvr32.exe /s stdole2.tlb
regsvr32.exe /s vsmgmt.dll
net start swprv
net start VSS

Step 3: Delete Shadow Copies

vssadmin delete shadows /all /quiet

Step 4: Close Command Prompt and Reboot

exit

Windows 7 | Server 2008 / 2008 R2

Step 1: Navigate to System32

cd %WINDIR%\System32

Step 2: Run VSS Service Repair Commands (copy and paste all at once):

net stop VSS
regsvr32.exe /s ole32.dll
regsvr32.exe /s oleaut32.dll
regsvr32.exe /s comcat.dll
regsvr32.exe /s vssapi.dll
regsvr32.exe /s es.dll
regsvr32.exe /s stdole2.tlb
net start VSS

Step 3: Delete Shadow Copies

vssadmin delete shadows /all /quiet

Step 4: Close Command Prompt and Reboot

exit

Alternative Method: Using PowerShell (Windows 10/11 & Server 2016+)

If you prefer using PowerShell, you can run this command set as Administrator:

# Stop VSS services
Stop-Service -Name VSS -Force -ErrorAction SilentlyContinue
Stop-Service -Name swprv -Force -ErrorAction SilentlyContinue

# Re-register COM components
$dlls = @(
    "$env:WINDIR\System32\ole32.dll",
    "$env:WINDIR\System32\oleaut32.dll",
    "$env:WINDIR\System32\comcat.dll",
    "$env:WINDIR\System32\vssapi.dll",
    "$env:WINDIR\System32\es.dll",
    "$env:WINDIR\System32\stdole2.tlb",
    "$env:WINDIR\System32\mscoree.dll",
    "$env:WINDIR\System32\vsmgmt.dll"
)

foreach ($dll in $dlls) {
    regsvr32.exe /s $dll
}

# Restart VSS services
Start-Service -Name swprv
Start-Service -Name VSS

# Clear shadow copies
& vssadmin delete shadows /all /quiet

# Verify
& vssadmin list writers

Post-Repair Verification

After completing the repair steps and rebooting, verify that VSS is functioning correctly:

Check VSS Writers Status:

vssadmin list writers

Expected output should show writers with status "Stable" (not "Failed" or "Unknown").

Check for Shadow Copies:

vssadmin list shadows

Check Event Viewer for Errors:

Open Event Viewer (eventvwr.msc)
Navigate to Windows Logs → Application
Look for VSS-related errors (search for "VSS" in the event logs)

Troubleshooting

VSS Writers Show as "Failed"

If VSS writers remain in a "Failed" state after repair:

Restart the system again
For SQL Server: Restart the SQL Server VSS Writer service (net stop sqlvss followed by net start sqlvss)
For Hyper-V: Restart the Hyper-V VSS Writer service (net stop hvvss followed by net start hvvss)

Commands Return "Access Denied"

Ensure you have opened Command Prompt with "Run as administrator"
Verify your user account has administrative rights

NovaBACKUP Still Fails After VSS Repair

Verify all VSS writers are in "Stable" state
Check Event Viewer for system errors
Run System File Checker: sfc /scannow
If issues persist, contact NovaBACKUP Support and provide system logs

VSS Service Will Not Start

Verify the VSS service is set to start automatically:
- Services.msc → Volume Shadow Copy → Set startup type to "Automatic"
Check Event Viewer Application log for error messages

Try disabling and re-enabling the service:

sc config VSS start= disabledsc config VSS start= auto

When to Use This Repair

Use this VSS repair procedure when you experience:

"VSS Writer failed" errors in NovaBACKUP
Backup jobs unable to complete
"Shadow copy not found" messages
Frequent "Connection to Backup Service stopped" errors
Event Viewer errors related to VSS or COM components
vshadow.exe or vssadmin errors during backup operations

VSS Command Line Repairs