Short answer:
Server-side signatures allow Xink to apply email signatures to emails sent from non-Outlook clients, such as Apple Mail (iOS), CRM systems, and third-party tools.
The email is routed through the Microsoft 365 mail flow, where Xink applies the signature configured in the Xink portal before the message is returned for delivery.
For Outlook clients, we recommend using the Xink Outlook Add-in, which applies signatures directly while composing emails.
Learn more → How to update email signatures in Outlook (Outlook Add-in)
What is Server-Side?
When server-side signatures are enabled, outgoing emails are routed through the Xink ReRouter hosted in Microsoft Azure.
The ReRouter:
- Intercepts outgoing emails in Microsoft 365.
- Checks for existing signature patterns or markers.
- Applies or replaces the signature using Xink data.
- Returns the email to Microsoft 365 for delivery.
Xink does not send the email. Microsoft 365 remains responsible for delivery.
This ensures consistent branding across emails sent from any device or system.
When to Use Server-Side Signatures
- Emails are sent from mobile devices or non-Outlook clients.
- You want to prevent users from editing signatures.
- Signatures do not need to be visible during email composition.
- You want to replace default signatures like "Sent from my iPhone".
Xink infrastructure is hosted in Microsoft Azure across multiple regions (US, EU, UK, Canada, Australia).
All communication is secured using TLS 1.2 encryption.
Processing Delay
Because emails are routed externally, a small delay may occur.
- Typical processing time: ~5 seconds
- Signature cache: ~20 minutes
Changes to signatures or user data may take a short time to appear.
Configure Server-Side
The Xink web console connects securely to Microsoft 365 and creates the required configuration automatically.
Start the Integration
- Go to Preferences in Xink.
- Select Integration.
- Click Microsoft 365 (Server-Side).
- Select Start Integration.
Authenticate with Microsoft 365
- Copy the device login code.
- Open the Microsoft login link.
- Sign in with a Microsoft 365 admin account.
Requires Exchange Administrator permissions (or higher).
Important Authentication Note
Do not close the window after login. The session is still completing authentication.
Create the Mail Flow Configuration
- Click Create.
- Xink will create:
- Transport rule
- Outbound connectors
Confirm the Configuration
If your domain appears, the integration is successful.
Click Save.
The transport rule is created disabled by default.
Enable it in the Exchange Admin Center.
Allow 15–20 minutes for changes to take effect.
Ensure that the connectors are enabled.
Server-Side Only Configuration
With this setup, all outbound emails receive signatures during mail flow processing.
Learn more → Server-side only configuration
Recommendation: Contact Xink support before enabling this setup.
Test the Server-Side Signature
Use the following marker to test signature insertion:
{EMAILSIGNATURE}Steps:
- Disable all four default signature selections.
- Add {EMAILSIGNATURE} to your email.
- Send a test email.
