Private Sub Command2_Click()
For x = 0 To List1.ListCount - 1
List2.AddItem List1.List(x)
List1.RemoveItem x
Next x
End Sub

For x = 0 To List1.ListCount - 1
这句有问题

For x = 0 To
这句有问题
改为：

for x=List1.ListCount - 1 to 0 step -1

好像没有问题

Private Sub Command2_Click()
For x = 0 To List1.ListCount - 1
List2.AddItem List1.List(x)
'List1.RemoveItem x
Next x
list1.clear
End Sub