Apex Tests fails with "An unknown exception occurred" when running all for "Local Namespace"

[PawelWozniak]

Summary

I am using new test explorer. When I run all tests for "Local Namespace" or "(Unpackaged Metadata)" then all tests are failing with "An unknown exception occurred".
When I click on single class like AccountTH_Test, tests are executed and results are fine.

Steps To Reproduce:

1. Open Test Explorer and click on run all tests for "Local Namespace" or "(Unpackaged Metadata)"
2. Test execution fails immediately with "An unknown exception occurred"

1. Click on AccountTH_Test "Run Test" button. Tests are executed in SF which takes time and we see proper results.

Expected result

All tests in Lacoal Namespace are run on SF and I see proper results.

Actual result

All tests fail immediately with an error "An unknown exception occurred"

Additional information

Feel free to attach a screenshot.

Salesforce Extension Version in VS Code: 66.10.1

Salesforce CLI Version: @salesforce/cli/2.133.4 win32-x64 node-v24.15.0

OS and version: Windows 11

VS Code version: 1.119

Most recent version of the extensions where this was working:
Never since this feature was introduced.

[svc-idee-bot]

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