Before proceeding, Back Up and Sync your iPhone, then disconnect it from your computer.
On the iPhone, go to Settings.
Go to Mail, Contacts, Calendars.
Go to Add Account.
From the list of account types, select Microsoft Exchange.
On the following screen:
Field Name: You Enter:
Username your OakID
Password your Oak password
The Description field will default to the e-mail address you entered - you can leave that as the default.
Click Next. There will be a delay while your iPhone talks to the server and checks these settings.
On/Off sliders for Mail, Contacts, and Calendars will appear. Verify the options you want to sync with your phone.
Once you have verified your syncing options, click DONE.
You should now be able to access your Exchange e-mail under the iPhone Mail application. If you had already configured another e-mail account on your iPhone, you will need to click the back arrows located at the top-left of the Mail window to get out to the account selection screen. Contacts and Calendars are accessed separately, through their respective iPhone applications. After setup, allow a few minutes for the data for these to synchronize.