Remote connect to SQLExpress

By default, the TCP/IP protocol is disabled in SQLExpress, turn it on in SQl Server Configuration Manager.

Double click that TCP/IP row to pop-up the details window, click on the IP Address tab, notice the TCP Dynamic Ports is not default 1433.

The connection string for remote client should look like:

Data Source=remote_host\SQLEXPRESS,2740;Database=…;User=…;Password=…