SMSMSE uses the File Transfer Protocol (FTP) to download Rapid Release updates. By default, Windows Firewall blocks FTP connections. In order to allow SMSMSE to use Rapid Release updates, you must create an exception allowing FTP transfers within the Windows Firewall configuration.
To create a Windows Firewall exception for FTP:
Once these steps have been completed, Rapid Release definitions for SMSMSE will now be allowed through the Windows Firewall.