Why is the Whois tool not able to gather any information?

Answer

Whois queries are done on remote port 43. Initially whois queries were done using a UDP port but this was changed to TCP. If you are using a firewall, and would like to perform whois queries, you need to configure a rule in your firewall that wlll allow connections to this remote port.

For example, in ISA Server Whois exists already in the Protocol Definitions and you can use it in a Protocol Rule to allow such connections. Or you can add a rule in IP Packet Filters as follows:

• In Filter Type check 'Custom'
• IP protocol = 'TCP'
• Direction = Outbound
• Local Port = Dynamic
• Remote Port = Fixed Port
• Remote Port number = 43