How do I specify this port in my connection string when I have SQL server running on a non-default port?

Windows Forms FAQs

How do I specify this port in my connection string when I have SQL server running on a non-default port?

The data source component of your connection string should contain the port right after the IP address (or name). It should be separated from the IP by a comma.

data source=192.168.123.1, port_number;

Take a look at the connectionstrings.com website for great information on several connection strings.

Contributed from George Shepherd's Windows Forms FAQ