Enable sender secret key validation

To enhance the security of Email Signature Server there is an optional mechanism to validate the authenticity of the sender.

Enable Secret Key Validation to Email Signature Server

1. Use a GUID generator to create a new value: Free Online GUID Generator.
2. Navigate to https://admin.exchange.microsoft.com/.
3. Go to Mail flow, then Rules.
4. Find the Templafy rule, likely named: templafy email signatures.
   • Click Edit.
   • Under the Do the following section, click the + button to add another condition.
   • Select Modify the message properties followed by set a message header.
     • Click the first Enter text and set the header name to Templafy-EmailSignatureServer-Secret.
     • Click Save.
     • Click the second Enter text and set the value to the GUID generated in Step 1.
     • Click Save.
5. Navigate to https://portal.azure.com/.
6. Open the Kubernetes service containing the Templafy ESS, likely named: templafyemailsignatureserver.
7. Under Kubernetes resources, select Workloads.
8. Select the email-signature-server-deployment.
9. Select YAML, then JSON in the main window.
10. Add the following as an environment variable in the env section, you can place this after the office365SmtpServerHostname block:
    

    { 
        "name": "templafyEmailSignatureServerSecret",
        "value": "<GUID>"
    },

11. Replace <GUID> with the value obtained in Step 1.

12. Click Review + Save.

13. Check the Confirm manifest changes checkbox and click Save.