I have version 10 Sp3, paid version. My MWI has stopped working on my 2 devices. One is an Aastra 6757i CT and the other is a Cisco 7975G. 2 things have changed since I've noticed this. I moved to SP3 and I've changed my router. I now have Untangle as my router Firewall. Is it possible Untangle is blocking the MWI packets? If it is, what do I need to do to resolve? Thanks all.