To setup an IMAP account on your iPhone, follow these steps:
1. Go To Settings --> Mail, Contacts, Calendars --> Add Account.
2. Touch "Other" at the bottom of the page.
3. Touch "Add Mail Account".
3. Fill out the Name, Email and Password Fields and touch "Next".
(The Description will auto populate based on your email domain. Change it if you want to call it something else like "Work" or "School".)
4. Fill out the Incoming and Outgoing Mail Server fields based on your mail server information and touch "Next" (Contact your administrator for this information).
5. If you see the message 'Cannot Verify Server Identity' touch "Continue".
6. If you receive and error indicating that you cannot connect using SSL touch "YES" to continue without using SSL.
7. Touch "Save" on the next screen.
Make sure your Sent Items and Deleted Items are set to use the server and not the iPhone.
Follow these steps to set these options (make sure you have emails in these folders in your email client on your PC so you iPhone will recognize the folders)
1. Under Settings --> Mail, Contacts, Calendars touch your account.
2. Touch "Advanced" at the bottom of the page.
3. Touch "Sent Mailbox" in the Mailbox Behaviors section.
4. Make sure Sent has a check mark beside it under On The Server. If not, touch "Sent" under On The Server to use the server's sent folder.
5. Back out to Advance by touching "Advanced" in the upper left corner then touch "Deleted Mailbox" to set up your trash folder.
Make sure "Trash" has a check mark beside in under On The Server by touching "Trash" it if it doesn't already have the check.
6. Touch "Advanced" in the upper left corner to back out.
7. Touch "Account" in the upper left corner.
8. Touch "Done" in the upper RIGHT corner to save your settings. (**Very Important step to make sure you save your changes.**)
Enjoy your mail!