32位可执行文件的C＃问题

Question

我使用Visual Studio 2015编写了这段代码：

static string strconnect = "Dsn=mx86";
static public string strDoc_key = "";
static public bool bPicFounded = false;
OdbcDataAdapter dr = new OdbcDataAdapter();

DataSet ds = new DataSet();
Thread thread = null;
static public OdbcConnection dataConnection = new OdbcConnection(strconnect);
static public string strInitialDirectory = "";

public frmMain()
{
    InitializeComponent();
    try
    {
        if (dataConnection.State != ConnectionState.Open)
            dataConnection.Open();
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}

private void frmMain_Load(object sender, EventArgs e)
{
    if (dataConnection.State != ConnectionState.Open)
    {
        this.Invoke(new MethodInvoker(delegate { this.Close(); }));
    }
    try
    {
       // this.Invoke(new MethodInvoker(delegate
       // {

            DataTable mydt = new DataTable();
            using (OdbcCommand ord = new OdbcCommand("", dataConnection))
            {
                ord.CommandText = "SELECT `AnläggningsNr` GroupID ,`Beskrivning` GroupName  from `Utrustningar` " +
                                  "WHERE (((`NivåUpp`)='TOP') AND ((`Enhet`)='00'))";

                mydt.Load(ord.ExecuteReader());

                cboGroups.SelectedIndexChanged -= cboGroups_SelectedIndexChanged;

                if (mydt.Rows.Count > 0)
                {
                    cboGroups.ValueMember = "GroupID";
                    cboGroups.DisplayMember = "GroupName";

                    cboGroups.DataSource = mydt.DefaultView;

                    cboGroups.SelectedIndex = 0;
                    cboGroups_SelectedIndexChanged(null, null);
                }

                cboGroups.SelectedIndexChanged += cboGroups_SelectedIndexChanged;
            }
    }
    catch (Exception ex)
    {
        MessageBox.Show("a)Message is: " + ex.Message);
    }

}

当我进行x86构建时，组合框用system.data.datarowview填充，但是当我制作x64构建时，它工作正常。

这个问题可能是什么原因？