1and1.com Exchange Settings
Add Exchange Account:
email: Address you use on 1and1 (when you sign in to Outlook Web Access, http://exchange.1and1.com)
username: EXCHANGE\eXXXXXXXXX
password: password
description: whatever
Click Next.
Click Accept if certificate error appears.
server: imap.exchange.1and1.com
Your username, password and description should have already been filled in from the last screen.
Click Next to Verify account.
Click Accept if certificate error appears.
Turn off any options you would not like to sync on your iPhone and then click Save.
Back out to the home screen and go to Email and then the Inbox of the new account.
Wait for the messages to download. If you get a certificate error, click Accept.
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If you are having problems and nothing is syncing - sign on to Outlook Web Access, then click Options (top right on firefox/safari) and then on the right click Mobile Devices. If your iphone is listed but you're not getting any response on your actual phone, delete the device then delete the account on the iphone as well. Power off your iphone (not just put it to sleep) and turn on again, and try everything again.
MacBook Pro, Mac OS X (10.5.4), iPhone v1 (2.0 software)