i think u cannot delete if the datasource is set. that will result in deletion of records. i use the following code to move items within llistboxes.
VB Code:
Private Sub cmd_SelAll_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmd_SelAll.Click
List2.Items.AddRange(List1.Items)
List1.Items.Clear()
End Sub
Private Sub cmd_Select_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmd_Select.Click
Dim n As Short
For n = 0 To List1.Items.Count - 1
If List1.GetSelected(n) = True Then
List2.Items.Add(List1.Items(n))
End If
Next
n = 0
Do While n <= List1.Items.Count - 1
If List1.GetSelected(n) = True Then
List1.Items.RemoveAt(n)
n = n - 1
End If
n = n + 1
Loop
List1.Focus()
End Sub
Private Sub cmd_Remove_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmd_Remove.Click
Dim n As Short
For n = 0 To List2.Items.Count - 1
If List2.GetSelected(n) = True Then
List1.Items.Add(List2.Items(n))
End If
Next
n = 0
Do While n <= List2.Items.Count - 1
If List2.GetSelected(n) = True Then
List2.Items.RemoveAt(n)
n = n - 1
End If
n = n + 1
Loop
List2.Focus()
End Sub
Private Sub cmd_RemAll_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmd_RemAll.Click
List1.Items.AddRange(List2.Items)
List2.Items.Clear()
End Sub
hope it helps