SQL: Microsoft SQL Server-login failed for user 'username' Solution

After the SharePoint project is transplanted to another test server (this server has a database for testing and the project wants to access this test database), runCodeMicrosoft SQL Server 2008-login failed for user 'username' error. This is because the Code does not establish a trusted data connection with the database when accessing the database (Note: The project accesses the database through "Domain Name \ User Name ).
The error message is as follows:

 

Solution:
Set the Authentication Mode of SQL servere to both SQL Server and Windows Authentication mode.
Procedure: Go to Start> Programs> Microsoft SQL Server 2008> SQL Server Management studio --> right-click the server name, select Properties> Security --> under Server Authentication, select SQL Server and Windows Authentication Mode
After the settings are complete, you must restart the server to make the changes take effect.