Message recall/revoke in Outlook & CodeTwo Email Signatures 365

Problem:

You would like to know if CodeTwo Email Signatures 365 supports message recall/replace capability in Outlook (Fig.1.) and email revocation for messages protected with Office 365 Message Encryption (OME).

Fig. 1. The message recall option available in Outlook for an email in Sent Items.

Solution:

Yes, both the message recall feature in Outlook and the ability to revoke encrypted emails work with CodeTwo Email Signatures 365 on board.

Recalling messages in Outlook

Regardless of the CodeTwo software, for the message recall functionality in Outlook to work as expected, the following conditions need to be met:

• Both the recipient and the sender need to belong to the same Exchange organization.
• To access the message recall feature, you, as the sender, must use Outlook for Windows, the new Outlook for Windows, or Outlook on the web (OWA). Outlook versions for different platforms do not support message recall yet.
• The message recall feature must be enabled for your Microsoft 365 tenant (the default setting). To check the current status of the feature, run Windows PowerShell, connect to your Exchange Online, and use the following cmdlet:

  Get-OrganizationConfig | select MessageRecallEnabled

  If you get False as the result, it means the feature is disabled. Use the following cmdlet to re-enable the feature:

  Set-OrganizationConfig -MessageRecallEnabled $true

• If you want to recall messages which have already been read by your recipient(s), a dedicated option must be enabled in the Exchange admin center (EAC). If you’re not sure what your tenant’s setting for this option is, sign in to EAC, go to Settings > Mail flow, and check if Allow users to recall messages read by the recipient is selected.

If you are sure all the above conditions are met, but you experience problems with the message recall functionality in Outlook when using the CodeTwo software, please contact our Support Team.

For more information on using and limitations of message recall in Outlook, see this blog article.

Revoking emails protected with Office 365 Message Encryption

No matter if CodeTwo Email Signatures 365 adds signatures in the cloud (after an email is sent) or client-side (directly in Outlook when you type a message), email revocation works well. However, keep in mind that:

• Email revocation works only with messages encrypted using Office 365 Advanced Message Encryption.
• You can only revoke messages sent to recipients that don't use a Microsoft 365 (Office 365) email account, or Outlook.com account. In other words, email revocation works only if your recipient (e.g. a Gmail or Yahoo! user) gets a link to the OME Portal, where they can read your message. 
• The revoke feature works differently than recall. The revoked message is not removed from recipients' mailboxes. Recipients simply can no longer access the revoked message via a link.
• For your users to add Outlook (client-side) signatures and then be able to revoke them, they need to use the modern CodeTwo Signatures Web Add-in for Outlook in Outlook on the web (OWA).
• In cloud (server-side) mode, messages need to be encrypted after emails are routed through the CodeTwo cloud service to get a signature.

Use the following links to a Microsoft article to learn how to:

• revoke an encrypted email in Outlook on the web
• revoke an encrypted email as an administrator (with PowerShell)