Question : How to secure email message in Exchange 2003

One of our user has concerns on how secure our email system is.

We are using front and back end exchange 2003 servers and only front end server has SSL cert installed for Outlook Web Access use.

How secure is exchange or how to configure exchange to secure emails?

Is adding encryption good idea? If so how do I add encryption on emails?

Thank you for your help.

Answer : How to secure email message in Exchange 2003

Ok, I didn't see the email certificates with regard to Comodo.

But yes, essentially it means that both parties need a certificate, but the receiving party needs the public part of the sender's certificate.