Hangs at Discovering Python Interpreters

[iain-palmer]

Type: Bug

Behaviour

I regularly find that I'm stuck with "Discovering Python Interpreters" following attempting to select a new interpreter.

Steps to reproduce:

Unclear how to reproduce exactly, but occurs when I try to select a Python interpreter.

I use multiple virtual environments; not sure if this is relevant.

Diagnostic data

Output for Python in the Output panel (View→Output, change the drop-down the upper-right of the Output panel to Python)

XXX

Extension version: 2025.6.1
VS Code version: Code 1.100.2 (Universal) (848b80aeb52026648a8ff9f7c45a9b0a80641e2e, 2025-05-14T21:47:40.416Z)
OS version: Darwin arm64 24.5.0
Modes:

• Python version (& distribution if applicable, e.g. Anaconda):
• Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): Unknown
• Value of the python.languageServer setting: Default

User Settings

languageServer: "Pylance"

testing
• cwd: "<placeholder>"
• pytestEnabled: true

Installed Extensions

Extension Name	Extension Id	Version
black-formatter	ms-	2025.2.0
cmake	twx	0.0.17
cmake-tools	ms-	1.20.53
compare-folders	mos	0.25.1
copilot	Git	1.326.0
copilot-chat	Git	0.27.2
cpptools	ms-	1.25.3
cpptools-extension-pack	ms-	1.3.1
cpptools-themes	ms-	2.0.0
debugpy	ms-	2025.8.0
docker	doc	0.7.0
figma-vscode-extension	fig	0.4.1
gc-excelviewer	Gra	4.2.63
git-graph	mhu	1.30.0
gitlens	eam	17.1.1
go	gol	0.46.1
isort	ms-	2025.0.0
jfrog-vscode-extension	JFr	2.13.9
js-debug	ms-	1.100.1
js-debug-companion	ms-	1.1.3
jupyter	ms-	2025.4.1
jupyter-keymap	ms-	1.1.2
jupyter-renderers	ms-	1.1.0
likec4-vscode	lik	1.31.0
makefile-tools	ms-	0.12.17
markdown-all-in-one	yzh	3.6.3
markdown-mermaid	bie	1.28.0
parquet-explorer	Ada	1.2.1
plantuml	jeb	2.18.1
prettier-vscode	esb	11.0.0
python	ms-	2025.6.1
rainbow-csv	mec	3.19.0
remote-containers	ms-	0.413.0
remote-explorer	ms-	0.5.0
remote-ssh	ms-	0.120.0
remote-ssh-edit	ms-	0.87.0
remote-wsl	ms-	0.99.0
restructuredtext	lex	190.4.10
ruff	cha	2025.22.0
simple-rst	tro	1.5.4
svgeditor	hen	2.9.0
swagger-viewer	Arj	3.1.2
vscode-containers	ms-	2.0.2
vscode-conventional-commits	viv	1.26.0
vscode-counter	uct	3.7.2
vscode-docker	ms-	2.0.0
vscode-eslint	dba	3.0.10
vscode-filesize	mkx	3.2.2
vscode-github-actions	git	0.27.1
vscode-icons	vsc	12.13.0
vscode-jest	Ort	6.4.3
vscode-js-profile-table	ms-	1.0.10
vscode-jsonnet	Gra	0.7.2
vscode-jupyter-cell-tags	ms-	0.1.9
vscode-jupyter-slideshow	ms-	0.1.6
vscode-language-babel	mgm	0.0.40
vscode-proto3	zxh	0.5.5
vscode-pull-request-github	Git	0.110.0
vscode-pylance	ms-	2025.5.1
vscode-schema	kuk	0.5.0
vscode-typescript-next	ms-	5.9.20250529
vscode-yaml	red	1.18.0
vscode-zipfs	arc	3.0.0
vsliveshare	ms-	1.0.5948

System Info

Item	Value
CPUs	Apple M3 Pro (12 x 2400)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	4, 4, 4
Memory (System)	36.00GB (0.14GB free)
Process Argv	. --crash-reporter-id 0d42e7c0-2394-4a1c-8f0b-51e08af8fd68
Screen Reader	no
VM	0%

A/B Experiments

vsliv368:30146709
vspor879:30202332
vspor708:30202333
vspor363:30204092
vscod805:30301674
binariesv615:30325510
c4g48928:30535728
azure-dev_surveyone:30548225
962ge761:30959799
h48ei257:31000450
pythontbext0:30879054
cppperfnew:31000557
dwnewjupyter:31046869
pythonrstrctxt:31112756
nativeloc2:31192216
5fd0e150:31155592
dwcopilot:31170013
6074i472:31201624
dwoutputs:31242946
customenabled:31248079
hdaa2157:31222309
copilot_t_ci:31222730
e5gg6876:31282496
pythoneinst12:31285622
bgtreat:31268568
4gafe986:31271826
c7cif404:31314491
996jf627:31283433
pythonrdcb7:31303018
usemplatestapi:31297334
0aa6g176:31307128
7bj51361:31289155
747dc170:31275177
pylancecolor:31314202
aj953862:31281341
generatesymbolt:31295002
convertfstringf:31295003
gendocf:31295004

[pdpark-wex]

I am also not able to select a Python interpreter. This used to work but stopped working recently (it broke a while back, too, and took a while to fix - I believe adding the setting "python.defaultInterpreterPath": ".venv/bin/python" fixed it last time).

This was the only solution I found that worked: reverting to the older "js" python locator with this setting: "python.locator": "js" - from here. Obviously not a great long term solution, but nothing else worked.

I tried disabling most other extensions, stopping/restarting vscode, and even commented out all of my settings at one point. Also tried Python: Clear cache per this, but it didn't work either.

MacBook Pro: Apple Silicon, OS version: 15.4.1
VSCode Version: 1.100.2 (Universal)
Python extension version: 2025.6.1

I am using UV and my Python virtual environments are .venv folders in my projects.

[karthiknadig]

@iain-palmer @pdpark-wex Can you share your logs from Output > Python?

For uv environments, can you try installing https://marketplace.visualstudio.com/items?itemName=ms-python.vscode-python-envs extension, and reload. It handles both uv activation, and installing package with uv.

[iain-palmer]

@karthiknadig somewhat unhelpfully, I appear to have solved the issue by removing some (~5) old venvs, so am unfortunately unable to reproduce the issue now - apologies.

I'm also using uv, so will try using the extension recommend.

[pdpark-wex]

Output > Python (with "python.locator":"js" commented out in settings.json):

2025-06-03 12:28:03.910 [info] Experiment 'pythonRecommendTensorboardExt' is active
2025-06-03 12:28:03.910 [info] Experiment 'pythonSurveyNotification' is active
2025-06-03 12:28:03.910 [info] Experiment 'pythonTerminalEnvVarActivation' is active
2025-06-03 12:28:03.910 [info] Native locator: Refresh started
2025-06-03 12:28:04.303 [info] > pyenv which python
2025-06-03 12:28:04.303 [info] cwd: .
2025-06-03 12:28:11.702 [info] > conda info --json

BTW: I have this in my settings.json: "python.defaultInterpreterPath": ".venv/bin/python"