[Previous title: How do you create warning message for all incoming external emails?]
I would like to add a line to any email coming from a domain other than our own with a message similar to the following:
WARNING: This email originated outside of OurCompany.
DO NOT CLICK links or attachments unless you recognize the sender and know the content is safe.
Ideally this would be above the actual message, so its the first thing you see when opening an email from any outside network
I have tried using 'Events' to complete this, but there is no action available to add to the message. Is there any built in way to accomplish this?