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Summary: SQL Server error 4064 arises when a user’s default database is inaccessible due to detachment or corruption. Solutions include connecting to a different database or changing defaults. For corrupt databases, Kernel SQL Database Recovery software effortlessly recovers data, ensuring integrity. Recovered files can be saved to any SQL Server version or an offline batch file, offering a seamless recovery experience.

In SQL Server, every user is linked to a default database. If a user logs in without specifying a database, the system uses this default database. However, if the default database is inaccessible or not found, SQL Server generates an error message indicating the issue.

Error Message:

Cannot open user default database. Login failed.
Login failed for user “RockySz.” (Microsoft SQL Server, Error: 4064)
SQL Server Error 4064

In this scenario, the user ‘RockySz’ attempts to access SQL Server. However, the server fails to locate the default database, resulting in an error. The system is unable to open the default database, leading to a failed login attempt.

Common Causes of the SQL Error 4064/4062

When the default database is not available during the connection, then it can be due to various reasons like the following:

  • The database is no longer in SQL Server.
  • The database is in suspect mode.
  • The database is configured for a single user only and is already being used by another user.
  • The database is detached from the user account.
  • The database is in RESTRICTED_USER state.
  • The database is in emergency status.
  • The database is in an offline state.
  • The user has been denied access.
  • The database is part of the database mirror.
  • The user account may be a part of many groups, and the database may be unavailable for one of those groups.
Solutions to the SQL Error 4064/4062

There are two methods that you can use to rectify the error:

  1. Connect with a different database.
  2. Change the default database.
  1. Connect with a different database
    If you are the Database Administrator, you can log in to your account and change the default database to the master database. Follow the steps:

    1. Start the SQL Server Management Studio. When the ‘Connect to Server’ wizard opens up, input the Server name, username, and password. Here, click the Options button.
    2. Here, you can see the ‘Connect to database’ option for making the connection. It is set for the default database for the account RockySz. Now you can type the name of any other accessible database or can also write the name of the master database..
      NOTE: Do not use the drop-down to select any other database because it can give the error.
    3. Click the Connect button, and this time the account will log in successfully.
  2. Change the default database
    You can also change the default database to any other database using the login properties. Follow the below steps:

    1. After connecting with your SQL Server instance, go to Security Folder and expand it. Select the Login folder and go to your login name. Right-click the login name and click Properties.
    2. In the bottom part, you can see the option ‘default database’. If it is blank, then it means that your default database has been disassociated with the account. Type the name of an accessible database and click OK.

You can also run the T-SQL command to alter the default database of your SQL account. Follow the command:


You can choose any method mentioned above to resolve the 4064 error. However, your default database might be inaccessible due to various issues such as MDF file corruption. That’s why you should try SQL Database Repair software to retrieve the information from the default database and save it to another database. The tool efficiently retrieves data from corrupted SQL databases, preserving integrity, and allows saving to live SQL Server or a batch file. Additionally, it’s user-friendly and compatible with the latest SQL Server versions.


Kernel SQL Database Recovery stands out as specialized software capable of instantly accessing and recovering corrupted SQL Server database files. You do not need to manually identify the corruption in the SQL database as the tool can recover entire data from any kind of corruption. Following recovery, you have the flexibility to save the files to any SQL Server database version. Immediate access is granted once the files are saved to a live SQL Server. Additionally, there’s an exclusive option to store data in an offline batch file at a secure location.

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