by explicitcons | 2026-03-09 09:33:31+00:00
We are excited to announce the release of *Set-OutlookSignatures v4.26.0*. This update marks a significant milestone in providing the most flexible and future-proof email signature solution on the market.

With this version, we are addressing the evolving needs of highly regulated industries and government sectors by introducing native support for M365 sovereign clouds, while simultaneously modernizing our core communication with Microsoft 365.

## Exclusive Support for M365 Sovereign Clouds
As organizations move sensitive workloads to localized, highly secure infrastructures, Set-OutlookSignatures is leading the way. We are proud to announce that v4.26.0 now supports the following sovereign cloud environments:

* *[Delos (Germany)](http://www.deloscloud.de):* Tailored for the specific security and compliance needs of the German public sector.
* *[Bleu (France)](https://www.bleucloud.fr):* The premier "cloud de confiance" for French government and critical infrastructure.
* *[GovSG (Singapore)](https://www.tech.gov.sg):* Supporting the Digital Government journey of the Singapore Public Service.

Due to its advanced architecture, *Set-OutlookSignatures is currently the only email signature solution on the market* supporting these infrastructures. You can find more information about this at [Set-OutlookSignatures.com](/).

Furthermore, we’ve introduced a flexible configuration allowing for any future sovereign cloud environments. Using the new `$CustomCloudEnvironments` variable, you can define endpoints even during soft-launch phases before they are officially published by Microsoft.

## Future-Proofing: Transitioning from EWS to Graph API
Microsoft has [announced the decommissioning of Exchange Web Services (EWS)](https://techcommunity.microsoft.com/blog/exchange/exchange-o...) in Exchange Online, starting later in 2026.

*Set-OutlookSignatures is already prepared.* In v4.26.0, we have transitioned to using the brand new *Microsoft Graph APIs* as the primary method for mailboxes hosted in Exchange Online. While a fallback to EWS is integrated for now, it will cease to function once Microsoft disables EWS later this year. For on-premises mailboxes, EWS support remains fully in place.

> *Action Required for Admins*
> To use the new Graph functionality and avoid service interruption:
> 1. Remove the delegated permission `EWS.AccessAsUser.All` from your Entra ID app.
> 2. Add the delegated Graph API permission `MailboxConfigItem.ReadWrite`.
> 3. For SimulateAndDeploy mode do the same for delegated and application permissions.

## Documentation & Architecture Updates
To help our users better understand how our solution scales and maintains compliance, we have added a new *'[Architecture considerations](/details#architecture-considerations)'* chapter to our technical documentation. This section provides a deep dive into how Set-OutlookSignatures interacts with your environment securely.

For a full list of changes - including fixes, updated modules and updated documentation - please refer to the [official v4.26.0 changelog](https://github.com/Set-OutlookSignatures/Set-OutlookSignatur...).

## Interested in learning more or seeing our solution in action?
Contact us or explore further on our [website](https://set-outlooksignatures.com). We look forward to getting to know you!