title: 'matplotlib' ImportError: DLL load failed: %1 is not a valid Win32 application
body: <p>I'm python2.7 64bits on a 64-bits os, and installed matplotlib 64 (matplotlib-1.5.1-cp27-none-win_amd64.whl), but have this import error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "sim.py", line 6, in &lt;module&gt;
      from Solution import *
    File "C:\Python27\My sim\Solution.py", line 6, in &lt;module&gt;
      import matplotlib.pyplot as plt
    File "C:\Python27\lib\site-packages\matplotlib\pyplot.py", line 114, in &lt;module&gt;
      _backend_mod, new_figure_manager, draw_if_interactive, _show = pylab_setup()
    File "C:\Python27\lib\site-packages\matplotlib\backends\__init__.py", line 32, in pylab_setup
      globals(),locals(),[backend_name],0)
    File "C:\Python27\lib\site-packages\matplotlib\backends\backend_tkagg.py", line 6, in &lt;module&gt;
      from matplotlib.externals.six.moves import tkinter as Tk
    File "C:\Python27\lib\site-packages\matplotlib\externals\six.py", line 199, in load_module
      mod = mod._resolve()
    File "C:\Python27\lib\site-packages\matplotlib\externals\six.py", line 113, in _resolve
      return _import_module(self.mod)
    File "C:\Python27\lib\site-packages\matplotlib\externals\six.py", line 80, in _import_module
      __import__(name)
    File "C:\Python27\lib\lib-tk\Tkinter.py", line 38, in &lt;module&gt;
      import FixTk
    File "C:\Python27\lib\lib-tk\FixTk.py", line 65, in &lt;module&gt;
      import _tkinter
  ImportError: DLL load failed: %1 nÆest pas une application Win32 valide.
  </code></pre>
  
  <p>Any idea?</p>