1.) Login to Outlook Web Access, then click on "Options", then "Mobile Devices". Select your iPhone, then click on "Wipe All Data from Device...".

2.) Confirm by clicking on "OK". The remote wipe process starts. It may take up to 60 minutes.

3.) After the remote wipe process is completed, you´ll get a confirmation e-mail. To sync again with Microsoft Exchange, you must remove your device from the list now. To remove the iPhone from the list, click on "Remove Device from List...".

4.) Confirm by clicking on "OK". The iPhone has now been removed.

5.) After the device is removed from the list, you will get an e-mail. You can now setup the device or a new one respectively to sync with your Hosted Exchange account.