Ensurepip fails ungracefully when mimetype is missing from Windows registry

[BlipRanger]

Bug report

A "WinError 5 Access is denied" error occurs when ensurepip (for python 3.10 and above) is run and there are missing/inaccessible mimetypes in the Windows registry. Because ensurepip is used in the Python installer, it also fails silently there, causing pip to never be installed without alerting the user to the issue. The line in which the error occurs is here: https://github.com/python/cpython/blob/024ac542d738f56b36bdeb3517a10e93da5acab9/Lib/mimetypes.py#L250 Bypassing that line and instead using self._read_windows_registry(add_type) (which is the fallback function I believe) fixes the problem. I believe that _mimetypes_read_windows_registry(add_type) needs to be able to fail more gracefully when it can't find a particular mimetype in the registry. I found someone else describing exactly the issue here.

Your environment

• CPython versions tested on: 3.10, 3.11
• Operating system and architecture: Windows 10 LTSC, x64

Linked PRs

• gh-122047
• gh-122786
• gh-122787

[huanghe2015]

Same thing happened with me ,Patrick and Stackoverflow.

[LucasEsposito]

Opened a PR to address this issue