Try something like this
VB Code:
  1. Option Explict
  2. mstrSave As String
  3.  
  4.  
  5. If chkboxuf1.Value = True Then
  6.     Dim lngIndex As Long
  7.    
  8.     For lngIndex = List1.ListCount - 1 To 0 Step -1
  9.         If List1.List(lngIndex) = "AAA" Then
  10.             [HL="#FFFF80"]mstrSave = List1.List(lngIndex).List[/HL]
  11.             List1.RemoveItem lngIndex
  12.         End If
  13.     Next

And then in the Click sub

List1.AddItem mstrSave