Using Office Online Server (optional)

Install and configure an Office Online Server for viewing and editing documents.

Before you begin

To support this feature an Office Online Server must be installed in your local environment.

As a substitute for Microsoft 365's online collaboration features, you can deploy an Office Online Server on your local network to enable simultaneous collaboration on Excel/PowerPoint/Word documents. This is essential for collaborating on encrypted documents.

The Office Online Server must be accessible from the client via the hostname that you configured in the Microsoft 365 Settings.

If the external access from devices outside of the corporate network or VPN is required, a public DNS record has to be created that points to the Office Online Server to make it publicly accessible on Port 443.

The hostname has to be resolvable from inside and outside the organization. One best practice would be to resolve to an internal IP when inside the corporate network, but to a public IP for clients outside the corporate network.

For a detailed list of requirements, please refer to Plan Office Online Server.

Note: This feature is intended to be used in combination with the OneDrive/SharePoint apps for reverse or forward proxies.

Procedure

  1. Install an Office Online Server in your local network. Refer to Deploy Office Online Server for an introduction to the topic.
    1. Install the January 2022 Cumulative Update for Office Online Server or a later one for the latest security patches as well as to address issues with the cache management of OOS that affect working with versioned documents in SharePoint/OneDrive.
      Note: Please refer to the official Microsoft documentation for instructions on how to Apply software updates to Office Online Server
  2. Configure the eperi sEcure M365 to use the Office Online Server.
    1. Navigate to the M365 Settings as outlined in the procedure for Configuring Microsoft 365 parameters.
    2. Ensure that the WOPI Client Type is set to Office Online.
    3. For WOPI Client URL (e.g., OOS URL), provide the URL to your Office Online Server.
    4. Click Submit.
  3. Alternatively, you can configure the OneDrive and SharePoint apps individually to be aware of the Office Online Server using the following steps.
    1. Office365 SharePoint App
    2. Office365 OneDrive App
    3. Office365 SharePoint Forward Proxy App
    4. Office365 OneDrive Forward Proxy App

What to do next

Continue with Using User Context for OOS Document Editing.