All our domain name portfolio management software tools (Domain Punch Pro, Watch My Domains ISP and Pro) include a diagnostic port 43 whois lookup tool.
This is available from the Config Tab > Popup Whois ribbon button (Tools > Popup Whois Tool menu in older versions).
To check a domain name type in the whois server and the domain name into the appropriate boxes and then click ‘Go’.

The port 43 whois tool is very handy if you have problems looking up domain names.
If the tool is unable to connect to any whois server, one of the following is true.
- Your internet connection is down
- Your computer security software, company network or ISP is blocking port 43 connections.
If the tool is unable to connect to a particular whois server alone, it is possible that your IP address is bannedat the whois server or the whois server itself is down.
Using whois.iana.org to find Whois Servers
In some cases you can use the whois tool to determine the valid whois serverfor a country or top level domain by querying whois.iana.org. For example to find the whois server for query whois.iana.org for it. Now look through the whois output and you will find the whois server listed as
Whois Server (port 43): whois.nic.it