Resolve MSSQL error : cannot connect to the USERNAME/SQLEXPRESS

 Follow these steps to resolve this error of mssql.

1. When you encounter this error, close the mssql serve management.

2. Press (window +R) , type services.msc and hit enter.

3. A list will appear. Search SQL Server(SQLEXPRESS).

4. As you click on it, click the start button on the top left corner.

5. Now your problem is solved open the mssql server management and you are good to carry your task.