Regression: Windows Desktop sandbox cannot establish TLS (SEC_E_NO_CREDENTIALS), causing dotnet restore NU1301

What version of the Codex App are you using (From “About Codex” dialog)?

26.707.31428

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Windows 11 Pro x64

What issue are you seeing?

Summary

After updating ChatGPT Desktop to version 26.707.31428, the Windows Codex sandbox can modify files and build .NET projects, but it can no longer establish TLS connections required for dotnet restore.

The same machine, project and user work correctly outside the Codex sandbox.

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Diagnostics already performedDiagnostics already performed

• Workspace permissions verified.
• NTFS ACL verified.
• Full Access enabled.
• Git operations work.
• File create/modify/delete works.
• Build succeeds.
• dotnet restore fails with NU1301.
• curl inside Codex fails with SEC_E_NO_CREDENTIALS.
• The same commands work outside the Codex sandbox.
• Avast Behavior Shield was disabled temporarily without changing the result.

<img width="382" height="362" alt="Image" src="https://github.com/user-attachments/assets/629b87ab-c591-481e-b59b-b72087d0b8f2" />

What steps can reproduce the bug?

1. Open ChatGPT Desktop 26.707.31428.
2. Open a local .NET workspace.
3. Enable Full Access.
4. Run:

dotnet restore LeliScan/LeliScan.slnx

or

curl.exe -I https://api.nuget.org/v3/index.json

What is the expected behavior?

dotnet restore completes successfully and curl can establish a TLS connection to https://api.nuget.org/v3/index.json.

Additional information

dotnet restore fails with:

NU1301:
Unable to load the service index for source
https://api.nuget.org/v3/index.json

curl fails with:

curl (35)
schannel:
AcquireCredentialsHandle failed:
SEC_E_NO_CREDENTIALS