Public Function IsFileInUse(ByVal strFilename As String) As Boolean 
 
        Dim ff As Integer = FreeFile() 
 
        If System.IO.File.Exists(strFilename) Then 
            Try 
                FileOpen(ff, strFilename, OpenMode.Binary, _
                  OpenAccess.ReadWrite, OpenShare.LockReadWrite) 
                IsFileInUse = False 
            Catch 
                IsFileInUse = True 
 
            Finally 
                FileClose(ff) 
            End Try 
 
        End If 
 
    End Function