You can remove the Exclaimer subscription with Microsoft 365 either partially to stop the signatures from being processed, through a particular deployment method or fully by uninstalling both Server-Side and Client-Side systems.
To uninstall the Exclaimer subscription for Microsoft 365:
Uninstall or disable server-side signatures for Exclaimer
You can temporarily disable or permanently stop emails from your organization routing to Exclaimer to have Server-Side signatures applied.
This will help if you are troubleshooting a mail flow issue, no longer wish to use Server-Side signatures or you have canceled your Exclaimer subscription.
You can uninstall server-side signatures only if you chose to install it initially.
For more information, see How to uninstall or disable server-side signatures for Exclaimer (Microsoft 365).
Remove the Exclaimer setup App from Microsoft Entra
As part of the setup process, Exclaimer installs various Azure apps; each app serves a specific purpose and is granted the minimum level of permissions required to fulfill its function.
It is important to remove the setup app to allow Exclaimer to have the right access to your tenant.
For more information, see How to remove the Exclaimer setup App from Microsoft Entra.
Uninstall the Exclaimer Signature Update Agent for Windows
You no longer want to use Client-Side signatures or you wish to upgrade to the Exclaimer Outlook Add-in. For this you need to uninstall Exclaimer Signature Update Agent.
You can uninstall the Exclaimer Signature Update Agent only if you chose to install it initially.
For more information, see Uninstall Exclaimer Client Signature Update Agent for Windows.
Uninstall the Exclaimer Outlook Add-in
You no longer want to use Client-Side signatures.
You can uninstall the Exclaimer Outlook Add-in only if you chose to install it initially.
For more information, see How to remove the Exclaimer Outlook Add-in app once installed?