Adding a mock Datatable in Unit Testing

I am Unit Testing one of my functions. Here is my code:

public void TestLabels()
{

  //Step 1: Creating a mock table with columns exactly like in the real table.
  DataTable table = new DataTable();

  DataRow mydatarow;
  mydatarow = table.NewRow();

  //Step 2: Adding the row as same as the Real Data!

  mydatarow["Name"] = "Test";
  mydatarow["Address"] = "00000 ST.";
  mydatarow["ZipCode"] = "77665";
  mydatarow["Tracking#"] = "";

  table.Rows.Add(mydatarow);

  foreach (DataColumn column in table.Columns)
    Console.WriteLine(column.ColumnName);

  //Step 3: Call method we are testing.
  var updateTable = IceTechUPSClient.Instance.CreateLabels(table);

  foreach (DataRow row in updateTable.Rows)
  {
    var trackingNumber = row["Tracking#"].ToString();
    Assert.IsFalse(String.IsNullOrWhiteSpace(trackingNumber), "Expecting tracking number generated for every row!");
    Assert.IsTrue(File.Exists(trackingNumber + ".gif"));
  }

}

Now I am getting an error: Column 'Name' does not belong to table. As you can see I have specified column name "Name" here and also added that particular row. Then why I am getting this error? Any help?

Thanks!