Hi from the team at Symprex!

Following the implementation of NAA authentication by Microsoft in February, we are seeing the disabling of legacy tokens on increasing numbers of customer Microsoft 365 tenants - this process is expected to be completed my Microsoft in June.

A very large percentage of customers have already completed the upgrade to the latest version of the add-in which we detailed in February. If you are already on v3, or joined Signature 365 after February, no action is required.

If the decision was made to enable legacy tokens and delay the upgrade, its is of utmost importance that the process is now completed and the upgrade is applied. Once legacy tokens are fully disabled, the previous versions of the add-in cannot function, and users with the Outlook add-in will not receive signatures until this is completed.

Details on the update process are noted here: Nested app authentication (NAA) and deprecation of Exchange legacy tokens


If you have any questions on the process, please contact our support team.

Hi from the team at Symprex!

We are happy to announce a number of new features introduced to Signature 365 in the last month, including the scheduling of disclaimers and additional Outlook settings.

Disclaimer Scheduling

Following requests from customers, we have introduced the ability to schedule the disclaimers applied to your signatures. The scheduling process works in the same method as campaigns, allowing disclaimers to be applied at a future date, and expiring when desired. As with signature rules and campaigns, disclaimers are applied in priority order, which can be updated using the "Reorder" button.

Following feedback from our Signature 365 agent customers, we have introduced the ability to change how the Signature 365 agent applies signatures across Outlook profiles and accounts.

These options can be found within the "Outlook (Classic)" integrations card. The defaults are as they have always been, to set for all accounts but not all profiles. Version 2.3.2 or later of the agent is required for these options to take effect. See How to install the Outlook (Classic) agent : Signature 365 Help Center for more information on this.

The team has also been busy with the additional improvements and fixes detailed below.

🛠 Other Enhancements

Improvement Injection: We've improved and added new mail clients to our email text separator detection.
Improvement We've improved the Database connector import to better handle errors, support Windows FIPS and adding scheduling.
Improvement We've improved our error messaging in the task pane when NAA authentication fails.
Improvement Outlook: We've updated and improved the diagnostics panel in the add-in.
Bug fix Portal: Using the "Change Folder" dialog no longer generates an error.
Bug fix Outlook: Legacy tokens being disabled no longer causes the add-in to hang in Outlook Classic event-based activation.
Bug fix Portal: Exporting active users for very large customers no longer times out.
Bug fix Portal: We've fixed an issue where Editors could not load domains.

Hello again from the team at Symprex!

📣 Folders for Signature, Campaign and Disclaimer templates

The team are excited to release the Folders functionality to help with the organisation and management of templates in Signature 365.

When you create a folder structure, this will apply to Signature, Campaign, and Disclaimer templates, displaying it consistently across all template types. You can create templates in folders and drag existing ones into folders and subfolders for easier management.

Your existing configuration will not be affected by this change, and the look and functionality of the portal will not change until a new folder is created.

You can read more about these changes in the article below:

Using folders in Signature 365

Hi again from the team at Symprex!

We have been working hard to ensure as smooth an upgrade as possible for all users of our Outlook Add-In to support the new authentication mechanism from Microsoft, Nested App Authentication. This has now been deployed by over 50% of Signature 365 tenants.

An update email was sent to all Signature 365 administrators advising of these changes in mid-January, Microsoft has recently updated documentation to define legacy disablement as the 17th February 2025.

For our customers that have not yet updated please note that this is a required change mandated by Microsoft if you are utilizing the Signature 365 Outlook add-in. If this is not completed, the add-in will stop working when legacy tokens are disabled by Microsoft. You can find information about upgrading in our Knowledge Base.

We have of course been working on additional fixes and improvements to the platform over the past couple of months, these are detailed below.

🛠 Other Enhancements

• IMPROVEMENT- Resolved timed-out user invites issue in the Partner Portal.
• IMPROVEMENT- You can now select multiple users or groups when creating or editing a rule in the portal.
• IMPROVEMENT- Customers are now able to cancel auto-renewal on their own.
• IMPROVEMENT - We refined the Campaigns view to give more information at a glance.
• IMPROVEMENT - vCards has exited the beta stage.
• IMPROVEMENT - Improved the responsiveness of search across the portal.
• IMPROVEMENT - Updated SMTP text replacement rules for better built-in signature replacement.
• IMPROVEMENT- Handle flakey network conditions better in the Outlook Add-In.
• IMPROVEMENT- The minimum requirement set has been updated for Outlook to 1.10, removing support for Outlook 2016 and 2019
• IMPROVEMENT- Active user CSV export now includes the current add-in version to track add-in deployment.
• BUG FIX- When assigning users to rules, the "Choose" dialog now remembers selections.
• BUG FIX- We've improved the identification of sent items to update in the sent-items-update, leading to improved item update rates.
• BUG FIX- SSO: case matching is too prescriptive for SSO logon causing issues connecting to Microsoft 365 accounts.
• BUG FIX - Plain text signature preview is incorrect in the Outlook task pane.
• BUG FIX - Add-in: Cannot reselect default signature if rule is set to None.
• BUG FIX - Campaigns incorrectly show as expired with an expiry date set.
• BUG FIX- Outlook Add-In dark mode is now supported on Mac.
• BUG FIX- Rule search is no longer case-sensitive.
• BUG FIX- Domain checks now correctly evaluate multiple MX records.

Hello again from the team at Symprex.

Our teams have been working hard to prepare for Microsoft's launch of a new method for Outlook add-in authentication called nested app authentication (NAA). NAA replaces the current authentication method, which Microsoft now refers to as "legacy tokens".

The preferred solution to this change is to upgrade the add-in to version 3.0. This will ensure that you are using the latest version of the add-in, and are able to take advantage of the newest updates and features.

As part of this process you will be asked to grant admin consent to two new permissions ("Maintain access to data you have given it access to" and "Sign in and read user profile"). This does not grant Signature 365 any additional access to data but is required for NAA to work.

Updating the Signature 365 modern add-in

If you are unable to perform the upgrade at this time, please see the following article for additional options:

Nested app authentication (NAA) and deprecation of Exchange legacy tokens

Hello all!

We're excited to introduce a fresh update to Signature 365 with major improvements to enhance your experience.

🔥 Signature, Campaigns, and Disclaimers Overhaul

You can now quickly see which campaigns and disclaimers are targeting specific groups or users, see when a campaign is scheduled or expired and have quick access to View, Edit or Copy right from the menu associated with each item.

🛠 Other Enhancements

As usual, we have been hard at work on the smaller improvements too

• Improvement Migration to .NET 8: We've upgraded to .NET 8, ensuring improved performance, stronger security, and enhanced reliability.
• Improvement Aptos and Aptos Display: These new fonts have been added to the visual editor, integrating with Microsoft's new default Office font.
• Improvement Quickly Remove Custom User Fields: It's now easier to remove custom field values from any user with just a few clicks.
• Improvement User Activity Insights: See when users were last active directly in their profiles for better management and tracking.
• Improvement Remove User-Specific Signature Overrides: Quickly delete signature overrides for individual users, streamlining signature management.
• Improvement More details in the Active User CSV export: You can now see the details of client types a user has accessed, making tracking adoption across Outlook platforms and server-side injection easier.
• Bug fix Alt Attribute Fix for Campaign Images: We've fixed an issue where "alt" attributes weren't added to campaign tracking images, reducing the risk of spam detection issues.

Hello all,

Signature 365 implemented a change freeze for the second half of September due to annual leave and other changes.

The development team have been busy working on several smaller features due to be released w/c 7th October:

• Support for the Aptos and Aptos Display fonts
• User information includes last active times and data sources for users
• Active user export now includes last connection times for all device sources
• "Remove all" button added for edited user attributes

Microsoft have also updated Outlook Mobile to support the onrecipientchanged event, meaning that your signatures will regenerate if the recipient is updated for internal/external recipients. Version 4.2425.0 or later is required to support this functionality.

The development team are also in the final steps of what will be the initial release for the folders functionality for Signatures, Campaigns, and Disclaimers. We are also in the final steps of a localization piece which will allow all users, including those using the add-in, to select the language they wish to use.

Initially, this step will provide the Danish and German languages to our customers, but this will be expanded to include additional languages, such as Spanish, French, etc etc. We will potentially be able to provide support in a language is requested by a customer moving forwards.

Hello again from the Signature 365 team.

Our August updates have focused on enhancing the product back-end and improving the portal's usability.

Our development team is currently implementing the initial phase of the folder structure feature. This will allow customers to organize signatures, campaigns, and disclaimers into a folder-based system, simplifying the management process for those with numerous templates.

The second step in this process involves implementing a permissions model that allows for the definition of access rights within the folder structure. This ensures that users can only access the contents of folders to which they have been explicitly granted permission.

Our scheduled June update window was delayed to allow our development team to resolve performance issues with signature generation affecting our EU customers.

Signature generation performance

Intermittent performance issues with signature generation were observed within our EU region as a result of an influx of new customers. Our teams worked to identify the root cause of these issues and released several improvements to the signature generation process.

These changes have directly led to greatly improved performance and reliability in all Signature 365 regions, along with improvements to signature generation logging.

Outlook signature caching

As a result of the changes to signature generation, we have also introduced several changes in how the signatures are cached within Outlook itself. These changes provide increased performance, improved resilience to connectivity issues, and reduced bandwidth required for signature data updates.

Display source for user field values in Portal

Edited or additional source data will now be displayed within the user details screen in the portal - the user below has data imported from on-premise SQL and AD sources.

Fields with updated information (AD, SQL or user-edited) will now be listed with the source used for signature generation

We are happy to announce that communications regarding changes to Signature 365 will now be posted within the Signature 365 announcements widget!

We will now post Release notes, Bug fix information and service Announcements within this platform, ensuring you have immediate access to the latest information and release details directly from the Signature 365 portal. Change logs for Signature 365 releases will now also be accessible from this platform.

Major updates which may change the user or portal experience will be posted in advance of release using an automatic alert on login, ensuring that you are always up to date with any changes that may affect you or your users.