Borrowed this code and it's working like a charm
Sub TestRun()
Call ListboxDeselectAllItems(MainForm.lstbxBrand_Converted)
End Sub
Public Sub ListboxDeselectAllItems(TheListBox As Object)
Dim TheItems As Variant
If TheListBox.MultiSelect = 0 Then
TheListBox = Null
Else
For Each TheItems In TheListBox.ItemsSelected
TheListBox.Selected(TheItems) = False
Next
End If
End Sub