1. Open the database management tool and log in using Windows first. Windows can only log in locally, so remote clients cannot log in.
2. Open Security - Login in turn. We can see that the system has built-in sa user, but it is disabled. 3. Right-
click the sa user and select Properties. In the properties interface, set password in "General" and in "Status" Set login to open.
4. Right-click the database connection and select properties. The default is windows mode in security. We changed it to sa and windows mode. The prompt will take effect after restarting.
We restart the database service.
After restarting, log in with sa. Log in success