Error in login to SQL Server

Question

When I want to connect to SQL Server 2008, I get this message:

Cannot connect to server.
Additional Information: Cannot open user default database.

Answer 1

This error (Microsoft SQL Server.Error:4064) occurs when the database which is dropped is default for some database user.

When the user tries to login and their default database is dropped the error shows up.

Cannot open user default database. Login failed. Login failed for user ‘UserName’. (Microsoft SQL Server, Error: 4064)

The way to resolve this is given here, summarized below.

The solution to log on is:

1. From the Connect to Server dialog, click Options
2. Change value of Connect to database: to any valid database on the server

The permanent solution to fix the server is to run SQL like:

ALTER LOGIN [test] WITH DEFAULT_DATABASE = master
GO

Answer 2

In my case this was due to a user being a member of multiple groups, each group having its own login. All groups' logins need to have their default database set to a database accessible to the user.

Other possible problems are listed at https://support.microsoft.com/en-us/kb/307864.

You can set each login with an invalid default database to have a default database of master (accessible to all logins):

alter login [loginname] with DEFAULT_DATABASE = master

Answer 3

The user default database is unavailable at the time of connection so that this error message will popup .SO check which server you tagged to that particular user to access whether it is online or offline mode.