ATTENTION: Windows Update KB3126593 issues problems with the local Windows Firewall of Windows Server 2012 R2.
We already opened a support ticket at Microsoft:
This is a known issue at Microsoft. They will provide an updated KB as soon as possible.
As CG make use of the local Windows Firewall this also affects CG in working correctly.
Please do not install KB3126593 on operating system instances CG is installed on.
If you already installed KB3126593 you can uninstall it via "Control Panel - Programs and Features - View installed updates".
As soon as we have further information from Microsoft we will post an update.