How to add Outlook signatures to emails sent from group mailboxes

Learn how to configure CodeTwo Email Signatures 365 to add signatures to emails sent as or on behalf of groups (Microsoft 365 group mailboxes, distribution lists and mail-enabled security groups). You can set up:

• A personal signature (with sender's details pulled from Entra ID / Azure AD) that is automatically added to an email sent as / on behalf of a group, as shown in Fig. 1.
• A dedicated group mailbox signature (which includes the group's details) that you can manually insert to an email.

Fig. 1. You can get your personal signature when sending an email as or on behalf of a group mailbox.

Use the links below for the setup instructions:

• How to add a personal signature to emails sent from group mailboxes
• How to set up a dedicated group mailbox signature

How to add a personal signature to emails sent from group mailboxes

Before you begin, ensure the advanced setting Change CodeTwo Outlook (client-side) signatures to match the email address in the From field is disabled for the add-in in CodeTwo Admin Panel, as shown in Fig. 2. Learn more about this setting

Fig. 2. To keep your personal signatures in emails sent from group mailboxes, disable this option.

Now, while composing an email in Outlook, if you select a group mailbox address (instead of your personal one) in the From field, your personal signature will remain in the email (Fig. 3.).

Fig. 3. You get your personal signature when sending an email as or on behalf of a group mailbox.

How to set up a dedicated group mailbox signature

Outlook (client-side) signatures can be manually added to emails sent on behalf of or as a group mailbox by choosing an appropriate signature in the CodeTwo Outlook add-in's pane. This scenario requires you to create a separate signature rule, which lists group delegates as senders.

Before you begin, ensure the advanced setting Change CodeTwo Outlook (client-side) signatures to match the email address in the From field is disabled for the add-in in CodeTwo Admin Panel, as shown in Fig. 2. Learn more about this setting

Now, go to app.codetwo.com and create a new Outlook (client-side) signature rule. For detailed steps, check out this article.

In the Senders step, click Add > Group members (inside organization) under the top list and select a group whose members will be able to use that signature, e.g. Customer Support, as shown in Fig. 4. You can also add individual senders (Add > Selected senders) instead.

Fig. 4. Configuring an Outlook signature rule for members of the Customer Support group.

Go to the Logic step and unselect (clear) the Set this signature as default for new messages and Set this signature as default for replies and forwards options, as shown in Fig. 5. This ensures the signature you're setting up isn't automatically added to emails sent from a regular (user) mailbox.

Fig. 5. Leave these options unselected.

Now go to the Design step and create a signature template for the group mailbox (see this quick guide for step-by-step instructions). Note that:

• If you use placeholders in a signature template, the information displayed in an email signature such as email address or telephone number will be taken from the Entra ID (Azure AD) account of a user who sends an email as or on behalf of a group mailbox.
• If you would like to present different information in the email signature e.g. the email address of the group mailbox or a helpline telephone number, you need to enter them manually when creating a signature template, without the use of placeholders.

Finally, click Apply & Close in the editor to save your template, and then click Save & Publish in the rule creation wizard to go live with your new email signature.

Now, when end users compose an email in Outlook, they can manually add the signature designed for the group mailbox from the add-in pane, as shown in Fig. 6.

Fig. 6. Inserting the signature designed for a group mailbox.