title: Properly set sa account for MSSQL 2012. Unable to login
body: <p>I made the following settings on my SQL Server 2012 as suggested in many tutorials:</p>
  
  <ul>
  <li>I set the server  authentication to "SQL Server and Windows Authentication mode"</li>
  <li>I set a strong password with enforced password policy with default database "master" to SA user</li>
  <li>I granted the SA user permission to connect to database engine and
  enabled his login.</li>
  </ul>
  
  <p>Yet when I try to login to the "localhost"
  through the SQL Server Authentication.</p>
  
  <p>it fails with:</p>
  
  <pre><code>Cannot connect to (local).
  ------------------------------
  Login failed for user 'sa'. (Microsoft SQL Server, Error: 18456)
  </code></pre>
  
  <p>Only possible way how can I login is still the Window authentication.</p>
  
  <p>My instance is named MSSQLSERVER. localhost\MSSQLSERVER is inaccessible.</p>