[BUG] Sign-in Validation Error After Sign-Out

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Bug Report: Sign-in Validation Error After Sign-Out

Version: 1.1.8629
Product: Cowork

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Summary
After signing out of an account on version 1.1.8629, users are unable to sign back in due to a persistent validation error.

Additional Context

• A second machine using the same account but running an older version 1.1.8359 (not upgraded to 1.1.8629) does not exhibit this issue — Cowork functions normally on that machine.
• This strongly suggests the bug was introduced in version 1.1.8629.

Impact
High — affected users are completely locked out of their account on the upgraded machine.

Workaround
Do not sign out on version 1.1.8629 until a fix is available. A machine running the previous version remains functional.

What Should Happen?

Expected Behavior
The user should be able to sign back in successfully without any errors.

Actual Behavior
A validation error is displayed upon attempting to sign in. The error persists and prevents the user from logging back into the application.

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce

1. Launch Cowork on version 1.1.8629.
2. Sign out of the current account.
3. Attempt to sign back in using the same account credentials.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.1.8629

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_