title: update-database: "A network-related or instance-specific error occurred while establishing a connection to SQL Server"
body: <p>I have a simple C# project. This is my connection string in my <code>web.config</code> for the database:</p>
  
  <pre><code>&lt;connectionStrings&gt;
     &lt;add name="DefaultConnection" 
          connectionString="Data Source=172.17.0.47;Initial Catalog=DevSystemListe;User ID=web_access;Password=123456" 
          providerName="System.Data.SqlClient" /&gt;
  &lt;/connectionStrings&gt;
  </code></pre>
  
  <p>I already made sure that this connection is working. I can connect to my database from the Visual Studio with this connection and I can also see the tables and data.</p>
  
  <p>When I want to update my database with <code>update-database</code>, this error occurs: </p>
  
  <blockquote>
    <p>A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)</p>
  </blockquote>
  
  <p>I uninstalled Entity Framework and then installed it again. Nothing changed.</p>