Control 'accessed from a thread other than the thread it was created on.

private void button1_Click(object sender, EventArgs e)
           {
               backgroundWorker1.RunWorkerAsync(2000);
           }
      private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
           {
               fillnotification();
           }


           public void fillnotification()
           {
               int pending = 0;
               if( Program.USERPK!=0){

                   DataTable dt = nftrans.getnotification();
                   pending = dt.Rows.Count;

                   String message = "You Have  " + pending + " Applications Pending For Approval";

                //   toolTip1.SetToolTip(lblStatus , message);
                  toolTip1.Show(message , this, lblStatus.Location);




               }
           }