Taken from Microsoft KB2664650
Microsoft push notification messages are not delivered to Lync mobile IOS and WP7 clients, when URL filtering is configured on Lync 2010 Edge Servers or office communication 2007 R2 Access Edge Server, apparently this is caused by:
with the release of the new Lync 2010 mobility service, Microsoft also has released what is called push notification service, many administrators like myself were surprised about this after reading Microsoft official Mobility guide and I bet many of them still doesn’t have a clear idea about how the push notification service works, and if is it required to be configured or not.
what is this Service used for ?
The Service is a cloud-based service located in the Lync online Data Center, it is used to send notifications to Lync mobile clients running on windows phone 7 and IOS based systems.
The push notification Service push notifications to mobile clients n the form of badges, icons, or alerts, even if the mobile application was inactive. Push notifications notify a user of events such as a new or missed IM invitation, missed calls, and voice mail.
now and after I have my hands on a brand new Lync 2010 mobile client it’s time to install and test this service.
so let’s get started, in this scenario Lync 2010 enterprise edition pool is deployed, running on windows 2008 R2 sp1 operating system.
Before beginning the installation it is recommended to review the official deployment guide to understand the mobility service concept
A) Install Lync 2010 Cumulative update 4 December 2011
since the Mobility Service requires Lync 2010 Cumulative update 4 December 2011 to be installed, ( you can get it from here) we will start by installing it in order to apply the Lync 2010 Hotfix KB 2493736.
1-on each Lync server download from here and run LyncServerUpdateInstaller.exe, select install updates and verify that now you have latest updated version installed, if not press install updates and wait until the updates are finished.