title: The type or namespace name does not exist in the namespace (are you missing an assembly reference?)
body: <p>I know that this question has been already asked, but I cannot find anything that can help solve my problem. </p>
  
  <p>I want to connect my <code>aspx</code> page (<code>Retete.aspx</code>) to a Microsoft SQL database. I'm getting this error on <code>Retete.aspx.cs</code>:</p>
  
  <blockquote>
    <p>Error 1   The type or namespace name 'GlobalClass' does not exist in the namespace 'ProiectSera' (are you missing an assembly reference?)
    The error points to this line of code:</p>
  </blockquote>
  
  <pre><code>ProiectSera.GlobalClass.Update(ValRefTempSol.Text, ValRefTempAer.Text);
  </code></pre>
  
  <p>Where <code>ProiectSera</code> is the project name, <code>GlobalClass</code> is the file where I make the operation on the db.</p>
  
  <p>My using statements are: </p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Web;
  using System.Web.UI;
  using System.Web.UI.WebControls;
  using ProiectSera;
  </code></pre>
  
  <p>The Target Framework is set to <a href="/questions/tagged/.net-4.5" class="post-tag" title="show questions tagged &#39;.net-4.5&#39;" rel="tag">.net-4.5</a>.</p>
  
  <p>What should I do to solve this error? </p>
  
  <p><strong>Update</strong>
  My GlobalClass.cs is:</p>
  
  <pre><code>using System;
  using System.Data;
  using System.Collections.Generic;
  using System.Linq;
  using System.Web;
  using System.Linq;
  using System.Text;
  using System.Threading.Tasks;
  using System.Data.SqlClient;
  using System.IO;
  using ProiectSera;
  
  using System.Data.Services;
  
  namespace ProiectSera.App_Code
  {
      public static class GlobalClass
      {
          static public void Update(string _param1, string _param2)
          {//function to update}
  }
  }
  </code></pre>
  
  <p>App_Code is a folder where GlobalClass.cs is. I tried and </p>
  
  <pre><code>ProiectSera.App_Code.GlobalClass.Update(ValRefTempSol.Text, ValRefTempAer.Text); //
  </code></pre>
  
  <p>but I had the same error. And I put the GlobalClass.cs in the project's root. I also removed the <em>.App_Code</em> from <code>namespace ProiectSera.App_Code</code></p>
  
  <p><strong>UPDATE1</strong>
  My Retete.aspx.cs is</p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Web;
  using System.Web.UI;
  using System.Web.UI.WebControls;
  using ProiectSera;
  using ProiectSera.App_Code;
  
  namespace ProiectSera
  {
      public partial class Retete : System.Web.UI.Page
      {
          protected void Page_Load(object sender, EventArgs e)
          {
  
          }
  
          protected void btnSave_Click(object sender, EventArgs e)
          {
              string intValRefTempSol;
              string intValRefTempAer;
  
   //           intValRefTempSol = ValRefTempSol.Text;
   //           intValRefTempAer = ValRefTempAer.Text;
  
  
     //         ProiectSera.App_Code.GlobalClass.Update(ValRefTempSol.Text, ValRefTempAer.Text);
              GlobalClass.Update(ValRefTempSol.Text, ValRefTempAer.Text);
  }
  }
  }
  </code></pre>