Unfortunately, Cox Communications DOES NOT support this automatic encryption. This means that any email that you send or receive from your e-mail account with them is sent in plain text and is open to eavesdropping, tampering, and forgery. They never responded when we reached out to them to see if it would be supported in the future. We would highly recommend that you use a different e-mail provider.
When an e-mail is sent from a provider that supports this encryption, it checks the receiving provider to see if it also supports this TLS encryption (Transport Layer Security). If it does, then the e-mail is encrypted in-transit to the receiving provider. If the receiving provider does not support TLS, then the e-mail is sent in plain text. This allows for universal compatibility.
You can feel confident that any documents or communication between us that is done over e-mail is secure and will not pose a risk to you.