It is possible on a Windows Phone to show more than one Exchange calendar. This is really convinient when having i.e. a private and a public Exchange hosted mailbox. Unfortunately opening another calendar is not as easy as it is through the Outlook client or Outlook Web Access, but still it can be done by following the steps below. Notice though that you need access to the mailbox in which it is hosted and there is no way to avoid syncing the contacts and e-mails at the first time. You can switch this off so it will not happen again, but the first time this will always be done.