SQL server opens 1433 client connection port

The client cannot be found or cannot be connected to the SQL database, mostly because Port 1433 of SQL is not opened or is blocked by the firewall.
It is easy to open port 1433 in SQL server: in the SQL server Configuration Manager, expand the network configuration of SQL server, select "MSSQLSERVER protocol", right-click the TCP/IP on the right, select Properties to go to the TCP/IP properties tab;

Select the IP address tab, where you can see the TCP port, which is 1433 by default. Finally, select "yes" in the "enabled" drop-down tab, and click "OK. If Port 1433 is enabled or cannot be connected, the firewall of the server must have blocked port 1433. To open the port blocked by the firewall, go here!