title: How can I fix my virtualenv?
body: <p>I just upgraded to OS X Mountain Lion and it killed most of my Python environment. I've reinstalled distribute 0.6.28 (<code>python distribute_setup.py install --prefix ~/Library/Python/2.7/site-packages</code>) &amp; pip 1.1 (<code>python setup.py install --prefix ~/Library/Python/2.7/site-packages</code>) from scratch. Then I installed <code>virtualenv</code> and <code>virtualenvwerapper</code> via <code>pip</code> without error, but the command <code>virtualenv ENVTEST</code> is failing as follows:</p>
  
  <pre><code>$ virtualenv ENVTEST
  New python executable in TESTENV/bin/python
  Please make sure you remove any previous custom paths from your /Users/x/.pydistutils.cfg file.
  Installing setuptools.................done.
  Installing pip....
  Complete output from command /Users/csh401/TESTENV/bin/python /Users/x/TESTENV/bin/easy_install /Users/x/Librar...ort/pip-1.0.2.tar.gz:
  /Users/x/TESTENV/bin/python: can't open file '/Users/x/TESTENV/bin/easy_install': [Errno 2] No such file or directory
  ----------------------------------------
  ...Installing pip...done.
  Traceback (most recent call last):
    File "/Users/x/bin/virtualenv", line 9, in &lt;module&gt;
      load_entry_point('virtualenv==1.7.2', 'console_scripts', 'virtualenv')()
    File "/Users/x/Library/Python/2.7/site-packages/virtualenv.py", line 942, in main
      never_download=options.never_download)
    File "/Users/x/Library/Python/2.7/site-packages/virtualenv.py", line 1054, in create_environment
      install_pip(py_executable, search_dirs=search_dirs, never_download=never_download)
    File "/Users/x/Library/Python/2.7/site-packages/virtualenv.py", line 654, in install_pip
      filter_stdout=_filter_setup)
    File "/Users/x/Library/Python/2.7/site-packages/virtualenv.py", line 1020, in call_subprocess
      % (cmd_desc, proc.returncode))
  OSError: Command /Users/x/.virtualenvs/env1/bin/python -x /Users/x/.virtu...nv1/bin/easy_install /Users/x/Librar...pport/pip-1.1.tar.gz failed with error code 2
  </code></pre>
  
  <p>My best guess is that it has to do with the fact that I was having trouble installing <code>distribute</code> and <code>pip</code> until I added the <code>--prefix</code> argument. But now while pip is working, it's not installing to the right location.</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>pip installed an older version of virtualenv. I ran <code>pip install -U virtualenv</code> and this ran without a hitch. Still getting an error, but a different error, now.</p>
  
  <pre><code>$ virtualenv -vvv TESTENV
  Creating TESTENV/lib/python2.7
  Symlinking Python bootstrap modules
    Symlinking TESTENV/lib/python2.7/config
    Symlinking TESTENV/lib/python2.7/lib-dynload
    Symlinking TESTENV/lib/python2.7/os.py
    Ignoring built-in bootstrap module: posix
    Symlinking TESTENV/lib/python2.7/posixpath.py
    Cannot import bootstrap module: nt
    Symlinking TESTENV/lib/python2.7/ntpath.py
    Symlinking TESTENV/lib/python2.7/genericpath.py
    Symlinking TESTENV/lib/python2.7/fnmatch.py
    Symlinking TESTENV/lib/python2.7/locale.py
    Symlinking TESTENV/lib/python2.7/encodings
    Symlinking TESTENV/lib/python2.7/codecs.py
    Symlinking TESTENV/lib/python2.7/stat.py
    Symlinking TESTENV/lib/python2.7/UserDict.py
    File TESTENV/lib/python2.7/lib-dynload/readline.so already exists
    Symlinking TESTENV/lib/python2.7/copy_reg.py
    Symlinking TESTENV/lib/python2.7/types.py
    Symlinking TESTENV/lib/python2.7/re.py
    Symlinking TESTENV/lib/python2.7/sre.py
    Symlinking TESTENV/lib/python2.7/sre_parse.py
    Symlinking TESTENV/lib/python2.7/sre_constants.py
    Symlinking TESTENV/lib/python2.7/sre_compile.py
    File TESTENV/lib/python2.7/lib-dynload/zlib.so already exists
    Symlinking TESTENV/lib/python2.7/warnings.py
    Symlinking TESTENV/lib/python2.7/linecache.py
    Symlinking TESTENV/lib/python2.7/_abcoll.py
    Symlinking TESTENV/lib/python2.7/abc.py
    Symlinking TESTENV/lib/python2.7/_weakrefset.py
  Creating TESTENV/lib/python2.7/site-packages
  Writing TESTENV/lib/python2.7/site.py
  Writing TESTENV/lib/python2.7/orig-prefix.txt
  Writing TESTENV/lib/python2.7/no-global-site-packages.txt
  Creating parent directories for TESTENV/include
  Symlinking TESTENV/include/python2.7
  Creating TESTENV/bin
  New python executable in TESTENV/bin/python
  Changed mode of TESTENV/bin/python to 0755
  MacOSX Python framework detected
  Symlinking TESTENV/.Python
  Testing executable with TESTENV/bin/python -c "import sys;out=sys.stdout;getattr(out, "buffer", out).write(sys.prefix.encode("utf-8"))"
  Got sys.prefix result: u'/Users/x/TESTENV'
  Please make sure you remove any previous custom paths from your /Users/x/.pydistutils.cfg file.
  Creating TESTENV/lib/python2.7/distutils
  Writing TESTENV/lib/python2.7/distutils/__init__.py
  Writing TESTENV/lib/python2.7/distutils/distutils.cfg
  Using existing distribute egg: /Users/x/Library/Python/2.7/site-packages/virtualenv_support/distribute-0.6.27.tar.gz
  Installing distribute...
    Running command /Users/x/TESTENV/bin/python -c "#!python
  \"\"\"Bootstra... main(sys.argv[1:])
  " -v --always-copy -U distribute
    Extracting in /var/folders/97/bds2slvx25s53xx1b_strvfs4xdq4b/T/tmpbqvjfq
    Now working in /var/folders/97/bds2slvx25s53xx1b_strvfs4xdq4b/T/tmpbqvjfq/distribute-0.6.27
    Installing Distribute
    running install
    Checking .pth file support in /Users/x/Library/Python/2.7/site-packages/
    /Users/x/TESTENV/bin/python -E -c pass
    TEST FAILED: /Users/x/Library/Python/2.7/site-packages/ does NOT support .pth files
    error: bad install directory or PYTHONPATH
  
    You are attempting to install a package to a directory that is not
    on PYTHONPATH and which Python does not read ".pth" files from.  The
    installation directory you specified (via --install-dir, --prefix, or
    the distutils default setting) was:
  
        /Users/x/Library/Python/2.7/site-packages/
  
    and your PYTHONPATH environment variable currently contains:
  
        ''
  
    Here are some of your options for correcting the problem:
  
    * You can choose a different installation directory, i.e., one that is
      on PYTHONPATH or supports .pth files
  
    * You can add the installation directory to the PYTHONPATH environment
      variable.  (It must then also be on PYTHONPATH whenever you run
      Python and want to use the package(s) you are installing.)
  
    * You can set up the installation directory to support ".pth" files by
      using one of the approaches described here:
  
      http://packages.python.org/distribute/easy_install.html#custom-installation-locations
  
    Please make the appropriate changes for your system and try again.
    Something went wrong during the installation.
    See the error message above.
  ...Installing distribute...done.
  Installing existing pip-1.1.tar.gz distribution: /Users/x/Library/Python/2.7/site-packages/virtualenv_support/pip-1.1.tar.gz
  Installing pip...
    Running command /Users/x/TESTENV/bin/python -x /Users/x/TESTENV/bin/easy_install /Users/x/Librar...pport/pip-1.1.tar.gz
    /Users/x/TESTENV/bin/python: can't open file '/Users/x/TESTENV/bin/easy_install': [Errno 2] No such file or directory
    Complete output from command /Users/x/TESTENV/bin/python -x /Users/x/TESTENV/bin/easy_install /Users/x/Librar...pport/pip-1.1.tar.gz:
    /Users/x/TESTENV/bin/python: can't open file '/Users/x/TESTENV/bin/easy_install': [Errno 2] No such file or directory
  ----------------------------------------
  ...Installing pip...done.
  Traceback (most recent call last):
    File "/Users/x/bin/virtualenv", line 9, in &lt;module&gt;
      load_entry_point('virtualenv==1.7.2', 'console_scripts', 'virtualenv')()
    File "/Users/x/Library/Python/2.7/site-packages/virtualenv.py", line 942, in main
      never_download=options.never_download)
    File "/Users/x/Library/Python/2.7/site-packages/virtualenv.py", line 1054, in create_environment
      install_pip(py_executable, search_dirs=search_dirs, never_download=never_download)
    File "/Users/x/Library/Python/2.7/site-packages/virtualenv.py", line 654, in install_pip
      filter_stdout=_filter_setup)
    File "/Users/x/Library/Python/2.7/site-packages/virtualenv.py", line 1020, in call_subprocess
      % (cmd_desc, proc.returncode))
  OSError: Command /Users/x/TESTENV/bin/python -x /Users/x/TESTENV/bin/easy_install /Users/x/Librar...pport/pip-1.1.tar.gz failed with error code 2
  </code></pre>
  
  <p>So it looks like my PYTHONPATH is somehow blanked out in the environment virtualenv is trying to build. That should be easy to fix, right?</p>