Exclaimer Outlook Add-in Version Release History

• Improved sign-in reliability when retrieving signatures on certain desktop versions of Outlook, including some older builds where sign-in could previously fail.
• Dependency updates and general under-the-hood improvements.

• Resolved an iOS authentication issue affecting some users

• Enhanced monitoring and observability
• Updated third-party dependencies

• Improved sign-in reliability
• Clearer error messages when sign-in issues occur
• General stability improvements, dependency updates

• Security and stability improvements
• Updated third-party dependencies

• Improved reliability of network requests. The Add-in no longer hangs when a request is slow or unresponsive.
• Fixed an issue related to how signature markers are handled, improving signature consistency.
• Security and stability improvements through updated third-party dependencies.

• Update includes dependency updates to patch third-party packages.

08/01/2026
Production

06/01/2026
Preview

• Update includes dependency updates and minor internal cleanup for improved stability.
  
  NOTE: The latest version of the Add-in (1.25.1000) is now available in AppSource. It may take up to 72 hours from the release date for the update to be available to all users.

• Resolved issue where the Add-in may incorrectly report as not compatible on Outlook for Mac for additional mailboxes.
• Resolved issue where a signature would not apply on a shared mailbox when opened in a new tab in Outlook Web Access (OWA) using 'Open another Mailbox'.
  
  NOTE: The latest version of the Add-in (1.25.900) is now available in AppSource. It may take up to 72 hours from the release date for the update to be available to all users.

• Update includes dependency updates and minor internal cleanup for improved stability.

• Update includes dependency updates to patch third-party packages.

• Fixed spacing issues in New Outlook.

• Update includes dependency upgrades and changes to the Add-in manifest.
• The Add-in will no longer request the User.Read scope from the admin during installation.

• Fixed an issue where some signature images on iOS were swapped to an unrelated cached image.

• Dependency and security updates.

• Fixed an issue where the Outlook Add-in did not retain the selected personal signature when sending from an alternative account (such as a shared mailbox).

13/05/2025
Production

 

12/05/2025
Preview

• Fixed issue where the Add-in signature was altered when an email was saved as a draft and reopened.
• Updated notification message for Rich Text Format messages. The signature will still be inserted.

06/05/2025
Production

 

02/05/2025
Preview

• Fixed issue with extra spacing when composing messages in New Outlook or Outlook on the Web.

29/04/25
Production

25/04/25
Preview

Fixed issues in the latest updates for Outlook, web, and Mac:

• The signature no longer changes size while typing.
• Scaling issues that occurred when the recipient viewed the message on a mobile device have been addressed.

22/04/2025
Production

02/04/2025
Preview

• New sign-in request form.
• Improved error message when legacy authentication token fails.
• Fixed issue when sending email to a contact group.
• Fixed an issue where a signature would be applied to an RTF email.   

03/03/2025
Production
 

24/02/2025
Preview    

• Security updates.

17/02/2025
Production

04/02/2025 
Preview

• Fixed authentication issues using new NAA tokens.
   
• Fixed an issue where user selected defaults were always applied regardless of rules. The defaults will now be applied based on configured rules.
   
• Updated the geolocation URL: https://outlookclient.exclaimer.net/cloudgeolocation
  
  This is used to determine the correct region for the Exclaimer subscription. This update is necessary following the retirement of retirement of the Azure CDN from Edgio.

• Product Survey.

• Added support for Recipient rules for mobile devices.

• Security updates.

• Fixed the issue when using a personal signature on an alternative account.

• Fixed an issue with the caching of old styling data.

• Added feature: Personal signatures for shared mailboxes.

• Fixed this error: "We were unable to sign you into Microsoft due to a time out." 

• A JavaScript version number has been added into the task pane of the Add-in; this will help to identify if the individual user is not running the latest version.

• Logs the version number and channel of the Add-in used.

• Fixed an 'operation failed' error that occurs when creating an email by sharing a document in MS Office.

• Removed registration of OnMessageSend events to improve reliability.

• Fixed security warning.
  
  No changes have been made to the Add-in functionality. 

• Bug fixes for error messages similar to:
  "Exclaimer is unavailable"
  "Add-ins are still running on this message"
  "Exclaimer is preventing this email from being sent"
  "Exclaimer add-in is taking longer than expected"

• Maintenance update.

• The Outlook Add-in name has been renamed to 'Exclaimer' (previous name was 'Exclaimer'). This change will be rolling out through the Microsoft Store over the next few days.

• The Outlook Add-in task pane can now be pinned so that it opens when emails are composed and replied to.

• Logging improvements.

• Text changes.

• Add-in updates default signature when 'From' address changes.*

      *Requires Outlook Version 2304 (Build 16327.20248) or above.

• Add-in supports default signatures on Outlook for Android (not yet available).

• Fix for cached logo image.

• Updated logo.

• Security enhancements.

The following has been resolved:

• Web-hosted images were not displayed in the preview of the signature.
• When forwarding an external meeting request, the add-in shows "domain is not an Exclaimer Customer"

The following has been resolved:

• A Client-Side signature which is set as default will not be replaced if there is no other signature with default settings enabled.

• Add-in supports default signatures for Outlook Desktop*
  
  *Requires Outlook Version 2110 (Build 14527.20226) or above

• Add-in supports Outlook Desktop