Lync Server 2010 Application Sharing failed to connect due to network issues
I have faced new issue with My Lync Server 2010 server. Lync 2010 calling, IM was working without any issues but application sharing or screen sharing with users fails after couple of minutes. The problem was with Windowsfirewall, so I have added rule allowing c:\program files\Microsoft Lync\communicator.exe” on my Group Policy.
After a gpupdate /force on the server and a gpupdate /force on my client machines, it worked without any issues.
Below screen shots will help you to add inbound rule for Microsoft Lync client,