We block several outbound ports for network security.

Blocked by default

You may request these blocks be removed by opening a support ticket.

• TCP port 25 (SMTP)
• TCP & UDP port 137 (NetBIOS Name Service)
• TCP & UDP port 138 (NetBIOS Datagram)
• TCP & UDP port 139 (NetBIOS Session)
• TCP & UDP port 445 (SMB over TCP)
• TCP port 1688 (Microsoft Key Management Server, inbound only

Permanently blocked

These ports are commonly abused for DDOS attacks. These blocks are permanent and cannot be removed.

• TCP & UDP port 17
• TCP & UDP port 19
• TCP & UDP port 1900
• UDP port 53413
• UDP port 11211