It may be required to disable the account of a database user in various scenarios. In SQL Server 2000 we had no such option to disable a database user. From SQL Server 2005 and onwards there is an option to disable the log in of a database user.
- Under security folder of your SQL Server instance, find and right click the user to whom you want to deny the login permission to SQL Server.
- Right click the user and click properties
- Following frame will be displayed, Go to status options
Now click OK and the selected user is no more able to log in to SQL Server.