I've been asked by a manager if we can accept secure emails from outside domains. In other words I work for company A (companyA.com) that runs an Exchange 2003 server with an ISA firewall for webmail and a spam appliance for smtp traffic. Company B wants to send one of my users a secure email, how do I set that up?
I have a public cert for CompanyA.com and I've read about how to secure internal email traffic using a Cert but does that apply to external as well?
Does it depend on the type of application Company B is using to secure its mail?
Does my spam appliance need to accept the secure email, is this not an Exchange issue at all?
As you can tell I'm grasping at straws here and any help would be appreciated.