I have a customer who has 5 unity 2.4.6.135 systems currently installed and networked. They would like to upgrade to 3.0. I have a few questions<br><br>1) is it true that in the 3.0 world. If the main Exchange server where all of the users are goes down, then the Unity server will still be able to process messages AND the user's will be able to retrieve them via the phone.?<br><br>2) What is the process to get a 2.4 system upgrade to 3.0. Any lost messages,greetings, mailboxes, etc? <br><br>3) Will 3.0 support a exchange 5.5 enterprise?<br><br>4) Is there any other documentation that will answer any further questions I may have regarding the upgrade?<br>Thanks in advance<br><br>