Hi Mirnes,

You have to handle DataBound of the ListBox event and remove whatever you
don't need:

protected void ListBox1_DataBound(object sender, EventArgs e)
{
    ListBox listBox = (ListBox)sender;
    // there are two methods you can use
    //ListItem listItem = listBox.Items.FindByText("ItemText");
    // or
    ListItem listItem = listBox.Items.FindByValue("3");
    if (listItem != null)
    {
        listBox.Items.Remove(listItem);
    }
}

hope this helps