Python 3.6下使用pip安装包报错问题咨询

Hey there! Let’s walk through the most common overlooked issues that cause this problem—even when you’ve added Python to your system PATH.

• PATH Order Matters
  If you have other Python versions (like 2.x) or programs with the same python.exe name installed, your system might be picking those first. Open a new cmd window and run where python—check if the top result points to your Python 3.6.4 installation folder (e.g., C:\Python36\python.exe). If not, edit your system PATH to move the Python 3.6 directory (and its Scripts subfolder) to the very top.

• You Didn’t Restart Your Cmd Window
  This is a classic mistake! When you modify the system PATH, any already-open command prompts won’t pick up the new changes. You need to close all cmd windows and open a fresh one for the updated PATH to take effect.

• Missing the Scripts Directory in PATH
  Even if you added the main Python folder, forgetting the Scripts subfolder (e.g., C:\Python36\Scripts) can break commands like pip. Double-check your system environment variables to ensure both directories are listed in PATH.

• Using the Wrong Command
  Unlike Linux/macOS, Windows doesn’t typically use python3 to call Python 3. Try running python first—if that launches an older version, use py -3.6 instead (this uses the Python Launcher for Windows, which should be included with your installation to target specific versions).

• Corrupted Installation
  If none of the above works, your install might be damaged. Uninstall Python 3.6.4 completely, download a fresh copy of the official installer, make sure to check the "Add Python to PATH" box during setup, and do a full reinstall. Restart your computer afterward to confirm.

内容的提问来源于stack exchange，提问作者umair durrani