Option Explicit

Const Source 	     = "C:\backup"
Const Destination    = "U:\backup"
Const DestinationOld = "U:\backup_OLD"

Dim objFSO
On Error Resume next

Set objFSO = CreateObject("Scripting.FileSystemObject")
If objFSO.FolderExists(Source) Then
   Dim msg
   msg = MsgBox("Press OK to begin backup to " & Destination, vbOkCancel)
   If msg = vbOk Then
       If objFSO.FolderExists(Destination) Then
           If objFSO.FolderExists(DestinationOld) Then
               objFSO.DeleteFolder(DestinationOld)
           End If
           objFSO.CopyFolder Destination, DestinationOld, True
           objFSO.DeleteFolder Destination
       End If
       objFSO.CopyFolder Source, Destination, True
       If Err Then
           MsgBox "Error!!!"
       Else
           MsgBox "Backup Complete"
       End If
   Else
       MsgBox "Backup cancelled by user."
   End If
Else
   MsgBox "Backup failed." & vbCrLf & "Source folder does not exist."
End If
Set objFSO = Nothing