Recover SQL Server login password using SQL Server Password Recovery Software
Firstly, you can recover SQL Server login password by going to Start menu » Programs » SQL Password Recovery Software.
Now you can select that particular Master .mdf file. The User Name and Password information will be enlisted in the panel of the window and then click on Open button.
In SQL Server, a list of all the users has been created by the tool. Unknown and Empty are the two values which was carried out by password column.
Unknown stands that you have a password presently but is encrypted.
Empty stands that you do have a password and you can login to their account without password.
Now take Attention: Further take a step it is highly recommended to take a backup of your Master .mdf and Master_log .ldf files as the tool will make changes to your Master database in the next step.
Now select the user whose password you want to reset. The software will show you an alert to take the backup of the Master .mdf and Master_log.ldf.
After continuation, you will set an Empty password for the selected user. Click Yes and go for Reset option.
Empty password for the selected user has been set by the tool.