title: Sql Server 2012 enterprise "sa" login failed. Error: 18456
body: <p>SQL server 2012. Windows 10 Professional.</p>
  
  <p>I enabled "sa" user account, and the authentication mode is set to "windows authentication and SQL server authentication". I set the password for "sa user account". but I cannot login into it. Error: 18456.
  <a href="https://i.stack.imgur.com/87B1O.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/87B1O.jpg" alt="enter image description here"></a></p>
  
  <p>I can successfully login into windows authentication.</p>
  
  <p>"sa" system administrator account status enabled.
  <a href="https://i.stack.imgur.com/FArEU.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FArEU.jpg" alt="enter image description here"></a></p>
  
  <p>I found many duplicate questions, but none solved the issue.</p>