login failed for user sa at SQL Server 2008 R2

问题

After upgrading to Service Pack 1, sometimes i got failed to login my server

at this time, Server Configuration Manager is like below

Do I need to change anything? thank you.

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Once I could login, Server Configuration Manager is like below

During the failure time, I try to start "SQL Server (MSSQLSERVER)" but got fail to start. What is wrong in my R2 express? Please share me your idea.

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After running "SQL Server (MSSQLSERVER)", I could login in to my server as 'sa'.

回答1:

Although my below snaps mention SQL Server 2008/express I would suggest to check for the below points.

• Check whether you need to put the local computer name prefix before your DB name

  

• If you connect using Windows authentication with the account you've created when you create your DB instance you can troubleshoot with right click database --> Database properties and select the below security option.

  

• Check sa login under security option by double clicking. You can change the password if required as below.

• Also if you see USER MAPPING option on the same properties view, check it and makesure sa is checked into the database you want to login.

  
  • Restart the SQL Server service (Shortcut: Winkey + R then services.msc)
  
  • Try to login again and good luck!

来源：https://stackoverflow.com/questions/17016681/login-failed-for-user-sa-at-sql-server-2008-r2