Resolve SQL Server in Express medium SA cannot log in

1, first log in with Windows Authentication, and then under Object Explorer, select the topmost server, right-click its properties, select Security on the left, change Windows mode to SQL Server and Windows Authentication mode, and the following login audit options-None.

2, under the Object Explorer under the database to open security--Login name--Select the SA right key property

Select General to delete or change the password and remove the enforced password slightly

Select status to set login to enable

3. Open the SQL Configuration tool (SQL Server Configuration Manager)

Restart the SQL service (you must reboot before you can log in)