SQL database connection to server error-unable to connect to XXX

Problem: An error occurred connecting to the server under Windows or SQL Server Authentication

How to resolve:

1. Check that the instance name is correct, as follows

Modify the changes according to the actual name of your computer as follows:

1) Microsoft SQL Server Management Studio is the official version:

2) Microsoft SQL Server Management Studio is an informal version, fill in:

The connection succeeded as follows:

2. If you are still not connected, check that the system SQL Service is turned on based on the correct server name:

1) in the Run panel input services.msc, open the system's service panel.

2) Right click on the following interface, click on the start option or restart

3) Re-open the following interface to connect

3. If the previous step is not connected, check whether the protocol in SQL Configuration Manager is modified:

1) Right click on My Computer, click Manage Options, open the Computer Management panel

2) Set the protocol and all to open,

3) Restart the SQL service

4) Finally reopen the Microsoft SQL Server Management Studio Interface Connection Database

Ps : Based on the above three locations, the SQL database connection problem is basically resolved. Due to the different configuration of each system, there may be differences in SQL database connectivity issues and will continue to be supplemented later.

SQL database connection to server error-unable to connect to XXX