SSLCertVerifyError: Certificate Verify Failed

Why This Happens

Python verifies SSL certificates by default. This error occurs when the certificate is expired, self-signed, or from an untrusted CA.

The Problem

import requests
response = requests.get('https://self-signed.example.com')

The Fix

import requests
# Update CA certs: pip install --upgrade certifi

# For custom CA:
response = requests.get('https://example.com', verify='/path/to/ca.crt')

# Dev only (not production!):
response = requests.get('https://localhost:8443', verify=False)

Step-by-Step Fix

1. 1

   Update CA certificates

   pip install --upgrade certifi.

2. 2

   Check the certificate

   Verify it is valid and from a trusted CA.

3. 3

   Provide custom CA bundle

   Point verify= to your CA file.