Sub test()
Dim Location As Variant
Location = ThisWorkbook.Path & "\export.xml"
Location = Application.GetSaveAsFilename(ThisWorkbook.Path & "\export.xml", filefilter:="Fichiers XML (*.xml),*.xml")
If Location = False Then Exit Sub
ActiveWorkbook.SaveAsXMLData Filename:=Location, Map:=ActiveWorkbook.XmlMaps("Root_Mappage")
End Sub