"Python Environment Tools (PET) failed" on a Ubuntu powered machine. Can't choose a Python interpreter for the project

[kirisakow]

This relatively new problem would occur on a Ubuntu-powered machine, with logs "Python Environment Tools (PET) failed", even in a project directory that has a .venv/ directory, which doesn't let me choose a Python interpreter for the project:

2026-04-22 15:28:15.432 [warning] [Global] Environment discovery failed after 0.0s.
  Error: process_crash - Python Environment Tools (PET) failed after 3 restart attempts. Please reload the window or check the output channel for details. To debug, run "Python Environments: Run Python Environment Tool (PET) in Terminal" from the Command Palette.
  If environments are not being detected correctly, please report this issue:
  https://github.com/microsoft/vscode-python-environments/issues/new
2026-04-22 15:28:15.435 [warning] [venv] Environment discovery failed after 0.0s.
  Error: process_crash - Python Environment Tools (PET) failed after 3 restart attempts. Please reload the window or check the output channel for details. To debug, run "Python Environments: Run Python Environment Tool (PET) in Terminal" from the Command Palette.
  If environments are not being detected correctly, please report this issue:
  https://github.com/microsoft/vscode-python-environments/issues/new
2026-04-22 15:28:15.437 [warning] [PyEnv] Environment discovery failed after 0.0s.
  Error: process_crash - Python Environment Tools (PET) failed after 3 restart attempts. Please reload the window or check the output channel for details. To debug, run "Python Environments: Run Python Environment Tool (PET) in Terminal" from the Command Palette.
  If environments are not being detected correctly, please report this issue:
  https://github.com/microsoft/vscode-python-environments/issues/new
2026-04-22 15:28:15.438 [warning] [Pipenv] Environment discovery failed after 0.0s.
  Error: process_crash - Python Environment Tools (PET) failed after 3 restart attempts. Please reload the window or check the output channel for details. To debug, run "Python Environments: Run Python Environment Tool (PET) in Terminal" from the Command Palette.
  If environments are not being detected correctly, please report this issue:
  https://github.com/microsoft/vscode-python-environments/issues/new
2026-04-22 15:28:15.440 [warning] [Poetry] Environment discovery failed after 0.0s.
  Error: process_crash - Python Environment Tools (PET) failed after 3 restart attempts. Please reload the window or check the output channel for details. To debug, run "Python Environments: Run Python Environment Tool (PET) in Terminal" from the Command Palette.
  If environments are not being detected correctly, please report this issue:
  https://github.com/microsoft/vscode-python-environments/issues/new

The PET extension happens to be missing, somehow:

1. Press ctrl shift p
2. Select Python: Run Python Environment Tool (PET) in terminal
3. See:

$ /home/username/.vscode-oss/extensions/ms-python.python-2026.4.0-universal/python-env-tools/bin/pet find --verbose
bash: /home/username/.vscode-oss/extensions/ms-python.python-2026.4.0-universal/python-env-tools/bin/pet: No such file or directory

[kirisakow]

💡 May it be related to #1467 ?

[kirisakow]

Removing the "python.useEnvironmentsExtension": true setting from User settings.json has fixed it.

As Python Environments extension developers say, the extension is currently under an ongoing rollout, thus behaving weirdly lately:

Note: The Python Environments icon may no longer appear in the Activity Bar due to the ongoing rollout of the Python Environments extension. To restore the extension, add "python.useEnvironmentsExtension": true to your User settings. This setting is temporarily necessary until the rollout is complete!