Only if you invite me over to stay in NZ for a month!


For now, just move the declaration out of the method.
Code:
Private WithEvents TheFileWatcher As FileSystemWatcher

Public Function fnWatchFolder(ByVal strFolderToWatch As String, ByVal strFileExtension As String) As Boolean

        ' Get the path to the directory we will watch.
        ' Make the FileSystemWatcher.

        TheFileWatcher = New FileSystemWatcher(strFolderToWatch, strFileExtension)
        TheFileWatcher.NotifyFilter = NotifyFilters.FileName ' Or NotifyFilters.FileName
        TheFileWatcher.EnableRaisingEvents = True
'        AddHandler FileWatcher.Changed, AddressOf OnChanged  You can use the WithEvents above to just xxx Handles TheFileWatcher.Changed event
        Return True
    End Function