In the RowDataBoundEvent, set the value of that cell to empty.
potected void grid_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView drView = (DataRowView)e.Row.DataItem;
DataRow drRow = drView.Row;
e.Row.Cells[7].Value = string.empty;
}
}
