FIX: "Unable to authenticate" or similar error with SharePoint Online

ZTN4621

This Zetadocs technical note applies to the following Zetadocs software (when using SharePoint Online): 

• Zetadocs for NAV (32-bit client).  

• Zetadocs Approvals. 

• Zetadocs Server. 

Symptom

Unable to archive new documents or view existing documents using Zetadocs, with an authorization error shown (e.g. “Unable to authenticate” | “Access denied” | “Invalid username or password” | “403 authorization denied”). 

The issue is persistent and will occur for all Zetadocs users on a system which has been impacted. 

Cause

This issue started occurring after Microsoft disabled an authorization method that Zetadocs (and other 3rd-party solutions) rely on to authenticate with SharePoint Online.  

Resolution

Updated versions of the above software are now available to install that will resolve the issue. These updates can be downloaded from the Software Updates page.

More information can be found using the links below.

INFO: What’s new in Zetadocs v11.1

INFO: What's new in Zetadocs Server v4.1

INFO: What's new in Zetadocs Approvals v2.2.25268

If you need any assistance, please contact your Dynamics partner. Alternatively, you can contact us directly (Support@equisys.com if you are in the UK, or Support@usa.equisys.com if you are in North America).

Last updated: 7^th October 2025 (DC/BB/NT)