Here are the steps to add an Hosted Exchange email account to your iPhone.
First, make sure you can login using Outlook Web App via https://exchange.infoquest.com. If you can login with your email address and password, you've confirmed you have the correct login information.
1. Select "Settings" icon from your iPhone home menu
2. Select Mail, Contacts, Calendars
3. Select Add Account...
4. Select the Exchange option.
5. Type in your full "Email Address".
6. Type in your "Password"
7. Type in the "Description".
8. Click on "Next"
9. Leave the Domain field blank.
10. When asked for the server enter: exchange.infoquest.com11. If you've typed in your email & password correctly, you'll get "check marks" on the right side to confirm everything is correct.
12. Next page, by default "Mail" is enabled. There you can enable "Contacts", "Notes" & whatever you'd like, then click "Save".
13. Once you've clicked the "Save" button, it will take you back to the email account list, hit your "Home" button, then your "Mail" icon.
14. There you'll see your list of email accounts, click the new account you've added and you'll see the email in your box.