for iphones and ipads:
- go to Settings
- go to Mail
- slide down to Accounts
- click on your Exchange account
- go all the way to the bottom and click Delete Account
- Delete from my iPhone
- Add Account
- Microsoft Exchange
- give the account a name
- click Next
- Sign In
- enter EID and EID password
- Duo Authenticate
- switch back from Duo to Settings
- slide the bars to the right for all the services you want to use so that they turn green
- it will ask about other contacts on your iphone. choose Keep on my iPhone
- click the back arrow on the top left where it says <==Mail
- scroll down to verify the settings on the Mail screen
- scrolling down, be sure to set the Default Account back to Exchange if you want Exchange to be the account you always want to send emails from with regularity. It will be the only choice if you only have Exchange/Outlook set up on your iphone/iPad.
- click the <==Mail again back to Settings
- for each service, Contacts, Calendar, Notes, Reminders, etc, set the Default account to use
- you should be ready to go