I got a tkMEssagebox.showerror showing up in a python tkinter application,
when somebody failed to login with the application.
Is it possible to have a url link in the tkMessageBox.showerror?
ie.

tkMessageBox.showerror("Error","An error occured please visit
  www.blahblubbbb.com")

and I want the www.blahblubbbb.com to be clickable?!
Short answer: "No!" message is a simple string, no interpretation like in some widgets of other frameworks is done. 
Longer answer: You could e.g. subclass+monkeypatch, to provide such feature.
tkinter tkMessageBox html link