The following updates for the Microsoft .NET Framework 4.5 are available that resolve some known issues that occur in a Microsoft Lync Server 2013 environment. Lync Server 2013 requires the installation of the updates to meet certain system requirements. If one of the updates is not installed on a Lync Server 2013 server, you will receive a message that informs you that the update is required.
2750147 An update is available for the .NET Framework 4.5 in Windows 7 SP1, Windows Server 2008 R2 SP1, Windows Server 2008 SP2, and Windows Vista SP2
2750149 An update is available for the .NET Framework 4.5 in Windows 8, Windows RT and Windows Server 2012
For more information about system requirements for servers that are running Lync Server 2013, go to the following Microsoft website: