步驟如下：

1. Run SQL Server Configuration Manager.

1. Go to SQL Server Network Configuration > Protocols for SQLEXPRESS.
2. Make sure TCP/IP is enabled.
3. 重啟SQL Server服務

So far, so good, and entirely expected. But then:

1. Right-click on TCP/IP and select Properties.
2. Verify that, under IP2, the IP Address is set to the computer's IP address on the local subnet.
3. Scroll down to IPAll.
4. Make sure that TCP Dynamic Ports is blank. (Mine was set to some 5-digit port number.)
5. Make sure that TCP Port is set to 1433. (Mine was blank.)
6. 檢查一下防火牆中1433埠是否開啟，如果是伺服器在雲，檢查一下網路安全組中是否打開了1433埠。

參考連結

How do I configure SQL Server Express to allow remote tcp/ip connections on port 1433?