title: An unhandled exception Additional information: External table is not in the expected format
body: <p>An unhandled exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll</p>
  
  <p>Additional information: External table is not in the expected format.</p>
  
  <pre><code>private void button1_Click(object sender, System.EventArgs e)
      {
          string path = @"C:\Projects\test.xlsx";
          string connStr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + ";Extended Properties=Excel 12.0;";
  
          string sql = "SELECT * FROM [Sheet1$]";
          using (OleDbDataAdapter adaptor = new OleDbDataAdapter(sql, connStr))
          {
              DataSet ds = new DataSet();
              adaptor.Fill(ds);
          }
      }
  </code></pre>
  
  <p>adaptor.Fill(ds); ==> Additional information: External table is not in the expected format.</p>