PrereqInstallFailed (Wmf2008R2) in Windows Lync Server 2010 Installation. This error occurs while the installer runs the following command: C:\Windows\system32\dism.exe /online /norestart /add-package /packagepath:C:\Windows\servicing\Packages\Microsoft-Windows-Media-Format- Package~31bf3856ad364e35~amd64~~6.1.7600.16385.mum /ignorecheck And the ERROR is: Resolution: Run the following command in the Read More …