Sql Server Connection Issues - Msg 18456

Now I'll try to help you understand the connection issues with Sql Server.
Today we will focus on the error

"Msg 18456, Level 14, State 1, Server , Line 1"
"Login failed for user ''."

This error is nothing but an authentication failure that involves a bad password or user name. So whenever you get a similar error be sure that is somthing related to user name or password.
And key to solve the issue is STATE number you get in the error.

• 2 and 5 : Invalid userid.
• 6 : Attempt to use a Windows login name with SQL Authentication.
• 7 : Login disabled and password mismatch.
• 8 : Password mismatch.
• 9 : Invalid password.
• 11 and 12 : Valid login but server access failure.
• 13 : SQL Server service paused.
• 16 : User don't have permission to log into Server.
• 18 : Change password required.

And as it seems you get the error Msg 18456 when you trying to connect Sql server in Sql Authentication.

Some points I like to add....

State 23 : Is one of the very rare errors, normaly happens when you try to connect to server when it is shutting down.

States 11 and 12 : When the Windows user trying to access the server and he doesn't have rights. Chances are you are on Windows Vista :).

- Mangal Pardeshi.