[BUG] Cowork: "Unable to start session. Sign in again to continue." on new session; composer draft is cleared and lost

Status Open
Maintainer reply None cached
Activity 0 comments · opened Aug 2, 2026

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] Cowork: "Unable to start session. Sign in again to continue." on new session; composer draft is cleared and lost

Environment

  • Claude Desktop 1.24012.9 (Electron 42.7.0, Node 24.18.0)
  • Windows 11 x64
  • Feature: Cowork, new session, model Opus 5

What happens

  1. Open a new Cowork session, type a long prompt into the composer.
  2. Press Enter.
  3. The session fails to start with the toast "Unable to start session. Sign in again to continue."
  4. The composer is now empty and the typed prompt is gone.

Expected
If the session cannot start, the composer draft should be preserved so the
prompt can be resubmitted after re-authentication.

Actual / root cause evidence
The client clears the draft before the session start succeeds. In
Local Storage the key composer-draft:epitaxy-draft is written with an
empty value at the moment of submit; there is no copy of the text in the
write-ahead log or in any older sstable record. The typed prompt is
therefore unrecoverable.

Notes
A similar issue was listed as fixed in v1.11847.5 ("signing in could leave
the app unable to start sessions until it was restarted"), so this looks
like a regression or a second cause with the same symptom.

Impact
Silent data loss of user-typed input.

What Should Happen?

Should've just started session according to prompt

Error Messages/Logs

Steps to Reproduce

just type new long prompt in cowork after a 3-4 hour break. claude code activity does not matter

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.24012.9

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

_No response_

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