When configuring the cumulative update for Lync Server 2010: November 2011 for Mobility on Windows Server 2008 Service Pack 1, you must perform additional steps to configure IIS 7.0 ASP.NET settings. The Lync Server 2010 deployment documentation for Mobility in the Lync Server 2010 Technical library has been updated to indicate these additional steps and their proper sequence.
Read more at source: http://blogs.technet.com/b/nexthop/archive/2012/01/19/update-installing-the-mobility-and-autodiscover-services.aspx
Cheers,
Anderson Patricio
http://blogs.msexchange.org/patricio
Twitter: @apatricio