In SGOS 6.7.1, the TLS defaults are version 1.1 and 1.2, which may not be supported by an older Windows server's SSL settings.
Here are the list of Window Servers and devices that do not support TLS 1.1 or TLS 1.2
- Windows XP
- Windows Vista
- Window Server 2003
- Window Server 2008
Enable TLSv1 on the default SSL device profile in ProxySG.