This will explain how to remove a cloud exchange email account from your iPhone or iPad.
There are actually two ways to do this since you can add the account via a profile or by manually setting it up.
Removing an exchange account/email account that was setup manually:
1. on the iPhone, go to Settings
2. go to Mail, Contacts, Calendars
3. click on the Exchange account
4. Scroll towards the bottom and click on “Delete Account”
Finally, you’ll get the Delete Account warning, click Delete Account to finish.
Wait, don't go... if yours does not have the delete button, proceed on!
1. Go to Settings
2. Go to General
3. Go to Profile and click Hosted Exchange:
4. Click on the Remove and you will get a warning like before. ALSO, BY REMOVING THIS PROFILE YOU WILL ALSO REMOVE THE CERTIFICATES and WIFI/VPN settings that the profile may also had included.