When you try to upgrade the operating system of a machine running Windows Server 2008 or Windows Server 2008 R2 to Windows Server 2012, the upgrade is blocked. This issue occurs if a beta version of the Dynamic IP Restriction module for IIS7 & 7.5 is installed on the server before the upgrade to Windows Server 2012 is attempted.
NOTE: This problem does not occur if the Dynamic IP Restriction module Beta 1 is installed on a Windows Server 2008 server that is then upgraded to Windows Server 2012.
NOTE: This problem does not occur if the Dynamic IP Restriction module Beta 1 is installed on a Windows Server 2008 server that is then upgraded to Windows Server 2012.