A Possible Cause of the [WinError 5] Error When Running pip install --upgrade
Records a debugging session for a WinError 5 access-denied error during pip install --upgrade cffi, traced to a running Python script holding the file being updated.
Machine-translated from the Chinese original.
Check whether a running Python interpreter is using (holding) the file being updated
After running pip install --upgrade cffi, I got a flat access denial (the message is in Chinese because Windows was):
ERROR: Could not install packages due to an EnvironmentError: [WinError 5] 拒绝访问。: '{path_to_python}\\python38\\lib\\site-packages\\_cffi_backend.cp38-win_amd64.pyd'
Consider using the `--user` option or check the permissions.Following the hint and adding --user after the command does work, but it doesn’t fix the underlying problem.
After Googling it, I found this might be related to file permissions, but running the command line as Administrator still produced the error.
Then I suddenly noticed a few Python scripts were running; after terminating them, cffi installed normally. So here’s a low-effort post just to note it down.