title: pip not installing to site-packages directory from within virtualenv when I use a requirements.txt
body: <p>I'm relatively new to running Python with virtualenv so this might be an easy fix, but I can't for the life of me figure out what's going on.  I'm running Windows 7 professional x64 with Python 2.7.5 installed I have installed pip and virtualenv.  I have a django project that I'm attempting to work on which I have cloned from a Heroku repository.  When I attempt to set up a virtualenv and install the requirements of my project I'm running into a strange error that I can't figure out.  I have everything setup as follows:</p>
  
  <p>Django project is placed in <code>C:\Users\xxx\PythonProjects\myProject</code></p>
  
  <p>I open a command prompt, cd to the myProject folder and execute the following command:</p>
  
  <pre><code>C:\Users\xxx\PythonProjects\myProject&gt; virtualenv --no-site-packages env
  </code></pre>
  
  <p>This should create a nice clean virtual environment for my project, so I go ahead and activate as follows:</p>
  
  <pre><code>C:\Users\xxx\PythonProjects\myProject&gt; Scripts\activate
  </code></pre>
  
  <p>The prompt changes to indicate my virtualenv has become active so I double check by "where"ing python and pip:</p>
  
  <pre><code>(env) C:\Users\xxx\PythonProjects\myProject&gt; where python
  C:\Users\xxx\PythonProjects\myProject\env\Scripts\python.exe
  C:\Python27\python.exe
  
  (env) C:\Users\xxx\PythonProjects\myProject&gt;where pip
  C:\Users\xxx\PythonProjects\myProject\env\Scripts\pip.exe
  C:\Python27\Scripts\pip.exe
  </code></pre>
  
  <p>Since it looks like virtualenv is functioning correctly I next attempt to pip the requirements file as follows:</p>
  
  <pre><code>(env) C:\Users\xxx\PythonProjects\myProject&gt; pip install -r requirements.txt
  </code></pre>
  
  <p>pip appears to run successfully installing all the packages I need.  However when I load up python the following happens (django is one of the packages in my requirements file):</p>
  
  <pre><code>(env) C:\Users\xxx\PythonProjects\myProject&gt;python
  Python 2.7.5 (default, May 15 2013, 22:44:16) [MSC v.1500 64 bit (AMD64)] on win32
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; import django
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  ImportError: No module named django
  </code></pre>
  
  <p>I then cd to the site-packages folder to find out what is going on and get the following:</p>
  
  <pre><code>(env) C:\Users\xxx\PythonProjects\myProject\Lib\site-packages&gt;dir
   Volume in drive C is Windows7_OS
   Volume Serial Number is 808F-577A
  
   Directory of C:\Users\xxx\PythonProjects\myProject\env\Lib\site-packages
  
  07/17/2013  02:16 PM    &lt;DIR&gt;          .
  07/17/2013  02:16 PM    &lt;DIR&gt;          ..
  07/17/2013  02:16 PM               237 easy-install.pth
  07/17/2013  02:16 PM    &lt;DIR&gt;          pip-1.3.1-py2.7.egg
  07/15/2013  09:16 PM           332,005 setuptools-0.6c11-py2.7.egg
  07/17/2013  02:16 PM                31 setuptools.pth
                 3 File(s)        332,273 bytes
                 3 Dir(s)  169,869,336,576 bytes free
  </code></pre>
  
  <p>It appears that my pip call failed to install ANYTHING into my site-packages folder, so python has no idea where to find my required packages.  Instead they appear to all be located in <code>C:\Users\xxx\PythonProjects\myProject\env\build</code></p>
  
  <p>If I use <code>pip install foo</code> without a requirements file, then everything works fine and the <code>foo</code> ends up in my site-packages folder.  Is there a way I can get this working with the requirements file, or am I going to have to manually install every package every time when using virtualenv?  Sorry for the likely overly long post, but I wanted to make sure that all relevant information is here.  Thanks for the help!</p>
  
  <hr>
  
  <p>Edit with additional information:</p>
  
  <p>It appears that my requirements file may be the source of the problem.  Only about half of the packages are being downloaded, the last being <code>django-polymorphic</code>.  The lines in my requirements file that specify that package and the following package are as follows:</p>
  
  <pre><code>django-polymorphic==0.4.2
  -e hg+https://bitbucket.org/fcurella/django-profiles@5c982ce7c040351fca9847a85dd4ff29f8a367e6#egg=django_profiles-dev
  django-sekizai==0.7
  -e git://github.com/divio/django-shop.git@0fb2258d27332166e3f76ad7cf7335c1f0a389b2#egg=django_shop-dev
  -e git://github.com/fivethreeo/django-shop-categories.git@345fb100f5f680e6ac2066f74f25515eb2cd9374#egg=django_shop_categories-dev`
  </code></pre>