The code was intended to run from a rule as the messages arrive, however it is easy enough to process a folder
Sub ProcessFolder()
'Graham Mayor - http://www.gmayor.com - 03/11/2016 
Dim olItem As Object
Dim olFolder As Folder
    Set olFolder = Session.PickFolder 'select the folder
    For Each olItem In olFolder.Items 'loop through the items
        If TypeName(olItem) = "MailItem" Then
            MoveToFolder olItem 'run the macro
        End If
        Exit For
    Next olItem
    Set olItem = Nothing
lbl_Exit:
    Exit Sub
End Sub