How to Enable SSL on an iPhone
A Secure Sockets Layer (SSL) is a tool that uses encryption to protect your privacy when emailing from your iPhone to an Exchange email server, and is available on most Exchange email servers that use IMAP (Internet Message Access Protocol) mail protocol. Whether you wish to enable SSL on your existing email account in your iPhone or add it to a new email during account setup on the iPhone, it is available in your iPhone's email settings and should be left on at all times to ensure privacy protection.
Push the bezel button, also known as the "Home" button, on your iPhone and swipe your finger on the arrow bar to unlock the iPhone.
Tap the "Settings" icon on your iPhone's screen, and tap the "Mail, Contacts, Calendars."
Tap the name of your existing email account under the "Accounts" section, and tap "Account Info" at the top of the screen. Tap "Advanced" and slide your finger over the "OFF" switch on the "Use SSL" tab to turn it on.
Select the "Authentication" tab, and select "MD5 Challenge-Response," "NTLM," "HTTP MD5 Digest" or "Password" as your authentication method. By default, most email servers use "Password" unless stated otherwise.
Tap the "Advanced" tab in the upper-left corner of the screen to return to the previous menu. Press the bezel button on your iPhone to return to the main menu.