pip install raise ValueError("check_hostname requires server_hostname") while VPN is on

Question

pip install <package> gives exception.

        raise ValueError("check_hostname requires server_hostname")
ValueError: check_hostname requires server_hostname

while VPN is on, let say. My only option is VPN . I can not turn it off. How to solve this problem. Pip Version pip 21.1.1 Python 3.9.5 Conda version conda 4.10.1

Here is a full exception.

    WARNING: Ignoring invalid distribution -rllib3 (c:\programdata\anaconda3\envs\pycharm\lib\site-packages)
WARNING: Ignoring invalid distribution -rllib3 (c:\programdata\anaconda3\envs\pycharm\lib\site-packages)
ERROR: Exception:
Traceback (most recent call last):
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\cli\base_command.py", line 180, in _main
    status = self.run(options, args)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\cli\req_command.py", line 204, in wrapper
    return func(self, options, args)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\commands\install.py", line 318, in run
    requirement_set = resolver.resolve(
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\resolution\resolvelib\resolver.py", line 127, in resolve
    result = self._result = resolver.resolve(
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 473, in resolve
    state = resolution.resolve(requirements, max_rounds=max_rounds)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 341, in resolve
    name, crit = self._merge_into_criterion(r, parent=None)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 172, in _merge_into_criterion
    if not criterion.candidates:
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\resolvelib\structs.py", line 139, in __bool__
    return bool(self._sequence)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\resolution\resolvelib\found_candidates.py", line 143, in __bool__
    return any(self)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\resolution\resolvelib\found_candidates.py", line 129, in <genexpr>
    return (c for c in iterator if id(c) not in self._incompatible_ids)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\resolution\resolvelib\found_candidates.py", line 30, in _iter_built
    for version, func in infos:
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\resolution\resolvelib\factory.py", line 258, in iter_index_candidate_infos
    result = self._finder.find_best_candidate(
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\index\package_finder.py", line 879, in find_best_candidate
    candidates = self.find_all_candidates(project_name)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\index\package_finder.py", line 824, in find_all_candidates
    page_candidates = list(page_candidates_it)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\index\sources.py", line 134, in page_candidates
    yield from self._candidates_from_page(self._link)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\index\package_finder.py", line 783, in process_project_url
    html_page = self._link_collector.fetch_page(project_url)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\index\collector.py", line 512, in fetch_page
    return _get_html_page(location, session=self.session)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\index\collector.py", line 422, in _get_html_page
    resp = _get_html_response(url, session=session)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\index\collector.py", line 120, in _get_html_response
    resp = session.get(
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\requests\sessions.py", line 555, in get
    return self.request('GET', url, **kwargs)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_internal\network\session.py", line 449, in request
    return super().request(method, url, *args, **kwargs)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\requests\sessions.py", line 542, in request
    resp = self.send(prep, **send_kwargs)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\requests\sessions.py", line 655, in send
    r = adapter.send(request, **kwargs)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\cachecontrol\adapter.py", line 53, in send
    resp = super(CacheControlAdapter, self).send(request, **kw)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\requests\adapters.py", line 439, in send
    resp = conn.urlopen(
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\urllib3\connectionpool.py", line 696, in urlopen
    self._prepare_proxy(conn)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\urllib3\connectionpool.py", line 964, in _prepare_proxy
    conn.connect()
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\urllib3\connection.py", line 359, in connect
    conn = self._connect_tls_proxy(hostname, conn)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\urllib3\connection.py", line 500, in _connect_tls_proxy
    return ssl_wrap_socket(
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\urllib3\util\ssl_.py", line 432, in ssl_wrap_socket
    ssl_sock = _ssl_wrap_socket_impl(sock, context, tls_in_tls)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\site-packages\pip\_vendor\urllib3\util\ssl_.py", line 474, in _ssl_wrap_socket_impl
    return ssl_context.wrap_socket(sock)
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\ssl.py", line 500, in wrap_socket
    return self.sslsocket_class._create(
  File "C:\ProgramData\Anaconda3\envs\PyCharm\lib\ssl.py", line 997, in _create
    raise ValueError("check_hostname requires server_hostname")
ValueError: check_hostname requires server_hostname
WARNING: Ignoring invalid distribution -rllib3 (c:\programdata\anaconda3\envs\pycharm\lib\site-packages)
WARNING: Ignoring invalid distribution -rllib3 (c:\programdata\anaconda3\envs\pycharm\lib\site-packages)
WARNING: Ignoring invalid distribution -rllib3 (c:\programdata\anaconda3\envs\pycharm\lib\site-packages)

Answer 1

You should try execute pip with --proxy paramenter like this:

pip --proxy <proxy> install <module>

Or you can try setting up environment-variables as explainded here https://pip.pypa.io/en/stable/user_guide/?highlight=proxy#using-a-proxy-server

Nevertheless, using a VPN should not prompt this kind of problemns, probably it's not well configured therefore, all the traffic doesn't go through it. Check that you have your 0.0.0.0 IP route pointing to the vpn first.

Answer 2

If you use VPN try to disconnect it, it will solve the problem. VPN changes the proxy server setting.

Answer 3

Only solution for me was to upgrade pip via whl.

Download the latest whl and then pip installed the pip upgrade (pip-21.2.4-py3-none-any.whl) from the whl.

Once I upgraded PIP, then PIP could install as expected.

Copying additional detail from comment as per request.

Go to pypi.org and search for pip.py (pypi.org/search/?q=pip.py&o=). Download the file to your local computer (pip-21.2.4-py3-none-any.whl). Then, at prompt, "pip install ". It fixed mine. Hopefully it does yours too!

Answer 4

There is another better way to solve this. Just need to upgrade pip version by using:

python -m pip install --upgrade pip