Dim str As String = "Test"
If Not System.IO.Directory.Exists(System.Windows.Forms.Application.StartupPath _
  & "\" & "Dokumentation") Then Return
        Using ofd As New OpenFileDialog
            ofd.Filter = "PDF|*.pdf"
            If ofd.ShowDialog() = DialogResult.OK Then
                File.Copy(ofd.FileName, Path.Combine( _
                  System.Windows.Forms.Application.StartupPath & "\" & _
                  "Dokumentation", Path.GetFileName(ofd.FileName)))  
                         My.Computer.FileSystem.RenameFile(Path.Combine( _
                         System.Windows.Forms.Application.StartupPath & "\" & _
                         "Dokumentation", Path.GetFileName(ofd.FileName)), str _
                         & ".pdf")
 
                File.Delete(ofd.FileName)
            End If 
End If              
        End Using

File.Delete(ofd.FileName)