title: "DLL load failed" when import cv2 (opencv)
body: <p>In [windows server 2012 R2 x64, python 3.7 64x]</p>
  
  <pre><code>pip install opencv-contrib-python
  </code></pre>
  
  <p>installed without any error .<br>
  and when I try to import it </p>
  
  <pre><code>import cv2
  </code></pre>
  
  <p>show me this error :</p>
  
  <pre><code>Traceback (most recent call last):
    File "test.py", line 1, in &lt;module&gt;
      import cv2
    File "C:\Program Files\Python37\lib\site-packages\cv2\__init__.py", line 3, in
   &lt;module&gt;
      from .cv2 import *
  ImportError: DLL load failed: The specified module could not be found.
  </code></pre>
  
  <p>and I see another topic about this error but their solution does not work for me :<br>
  - <a href="https://stackoverflow.com/questions/43184887/dll-load-failed-error-when-importing-cv2">DLL load failed error when importing cv2</a><br>
  - <a href="http://answers.opencv.org/question/69587/failure-to-import-cv2-in-python-dll-load-failed/" rel="noreferrer">Failure to import cv2 in python : DLL load failed</a><br>
  - and a lot of pages in <a href="https://stackoverflow.com/search?q=DLL%20load%20failed.">here</a> <br><br>
  some of them say about that problem because anaconda, and I don't have anaconda even. and many say that problem 32 or 64 version, I try both and disappointment. many about system variables...
  <br>
  what <code>dll</code> failed to load? cv2? why?</p>
  
  <p>what i try till now:</p>
  
  <ul>
  <li><p>change python version : 3.5, 3.7, 2.7 in 86x and 64x (uninstall complete last version and delete all remain files in program files ... then install new one)</p></li>
  <li><p>try with another packages like : opencv-python, opencv-contrib, try install specific versions with .whl (in some topic i read about this so install <strong>numpy-1.14.5+mkl-cp37-cp37m-win_amd64.whl</strong> and <strong>opencv_python-3.4.3+contrib-cp37-cp37m-win_amd64.whl</strong> but anything not change)</p></li>
  <li><p>import numpy before cv2 for every test</p></li>
  <li><p>installed Microsoft Visual C++ 2015 Redistributable Update 3 , 2008 , 2010 , 2017 for 64x</p></li>
  </ul>
  
  <p><strong>UPDATE</strong><br>
  <strong>NEXT 2 DAY</strong></p>
  
  <p>I try to manage missing <code>dll</code> base on <em>dependency walker</em> that mention in bellow post, download all <code>dll</code> and put them in system 32, its a good clue but not solve the problem.</p>
  
  <p><strong>DAY 4,5</strong></p>
  
  <p>my next step , trying compile OpenCV in my machine , install visual studio 2012 + cmake and base on <a href="https://docs.opencv.org/3.4/d5/de5/tutorial_py_setup_in_windows.html" rel="noreferrer">document</a> compile 2 version , 64x and 32 , compiling have a lot of problem itself  (like missing some lib from c lang and need to install <em>Visual C++ Redistributable for Visual Studio 2012</em> ...) and I resolve all of them ,then I have 2 success compiled version but both have the same problem with missing <code>dll</code>, the compile process is so slow and give 2 day from me. so if fail on this mission :/ I search for a new way...</p>
  
  <p><strong>DAY 6</strong></p>
  
  <p>my next step is to try to run OpenCV in my machine with docker ( I try but docker windows just install on windows 10 and windows server 2016) so I search for an alternative. I found Vagrant that work like docker but with VM (visual box) today my time spend for this articles, it's amazing, the concept of docker and vagrant is so Attractive, and I play with this like that I have new puzzle :)
  first error show on ... and limitless errors go on :</p>
  
  <p><strong>Day 7</strong></p>
  
  <p>Vagrant tests failed too because my windows server 2012 is a vb machine (visual server) and run a visual box in another visual box impossible!
  so I need new clues :</p>
  
  <p><strong>Day 8-9</strong></p>
  
  <p>try install vagrant with VMware , I download VMware, unfortunately this plugin is not free (79$) so I try to work with <a href="http://pythonanywhere.com" rel="noreferrer">pythonanywhere.com</a> that <em>'gives you access to machines with a full Python environment already installed.'</em> in this free account, you can't openurl with urllib , and more limit...
  so I wanna try to install ubuntu in VMware my self... I read here results after work. it's Impossible with same reason vb (visual box)</p>