This often happens in corporate environments where firewalls or proxies intercept traffic using self-signed certificates that pip does not trust.
pip install cython --trusted-host pypi.org --trusted-host files.pythonhosted.org Use code with caution. 3. Specify the Index URL Manually download error on https //pypi.org/simple/cython/
On some systems, especially macOS or manual Python builds, the ssl module might be missing or misconfigured, leading to "Max retries exceeded" errors. Troubleshooting and Fixes This often happens in corporate environments where firewalls
The first step is always ensuring your package manager is current. Modern pip versions have better handling for HTTPS and modern security protocols. python -m pip install --upgrade pip Use code with caution. 2. Bypass SSL Verification (Use with Caution) Specify the Index URL Manually On some systems,
Downloading Cython from the Python Package Index (PyPI) simple index is a standard part of many Python development workflows, but it can occasionally fail due to network configurations, security settings, or environment issues.
Depending on the specific error message received, you can try the following solutions: 1. Upgrade Pip