How to add an 'External' tag at the top of emails received from external sources

Relevant Product: Signature Manager Exchange Edition

Scenario

You would like to tag incoming emails to state whether they came from an external source.

Resolution

To achieve this,

1. Create a new template and add text to the signature design with the word 'External Mail'.
   Ensure this is above both of the reply separator fields.
   
   Caution: Ensure that the 2 separators, as displayed in the screenshot below are not edited or deleted. Doing so will likely cause problems with the location of the 'External Mail' text.
   
   
2. As required, add highlighting or edit the font of this text.
   It should now appear similar to this:
   
   
3. Save this template.
   
   
4. Now, create a policy to apply this signature. In condition select the appropriate fields to state that the sender is external and the recipient is internal:
   
   
   
   With both of these configured your external mail will now be processed by Signature Manager and have the 'External Mail' tag added at the top of any mail coming into your business.