Question : Error adding user mapping in sql server 2005

Hello,
  I just restore a database in SQLserevr 2005. Now I am trying to add the loging.

In SSMS 2005 I did teh following
Select security
Select the user
Select user mapping
click the checkboc netx the user name and enter the username and default schema
Select db owner and press ok


I get the error " user group or role  '<dbusername>' already exist in the current database

How do I fix this error.

Thanks

Answer : Error adding user mapping in sql server 2005

Try:
USE <DB>
GO
EXEC sp_change_users_login 'Auto_Fix', '<user>'
GO