I got the new 4S phone, set up email, and am able to receive email fine. I can send email to others on the same domain name, but when I send it outside the domain, I get an error message "Cannot Send Mail - A copy has been placed in your Outbox. The receipient "email@example.com" was rejected by the server." I'm not on any wifi system, only through verizon. Any ideas?
The problem may be with relaying. If your "from" address in an email is from a different domain than the domain that receives your email (e.g. using xxx.mac.com to send emails and you have one that is "from" firstname.lastname@example.org) then the server may reject your email; they do that to block spam that uses a server's address.
If you check the settings for the outgoing Mail Server, primary server, be sure to enter the user name and password. These may be labeled as "optional", but enter them still.