---
title: "Error -1020 Sharing Violation"
slug: "error-1020-sharing-violation"
updated: 2023-11-09T01:23:34Z
published: 2023-11-09T01:26:19Z
canonical: "docs.retrospect.com/error-1020-sharing-violation"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.retrospect.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Error -1020 Sharing Violation

Resources

Retrospect uses VSS (Volume Shadow Copy Service) which is built into Windows to copy open files. On Windows, Retrospect uses the ROFF.sys filter driver.

Check the Retrospect License Manager (Configure>Licenses) to make sure you have the Open File Backup Add-On in your copy of Retrospect. If you don’t have the Open File Backup add-on, make sure you close all program prior to the backup.

Last Update: February 14, 2012