Claude Desktop App: Cowork tab stuck on 'Sending request' - UUID validation error

Resolved 💬 16 comments Opened Jan 22, 2026 by terencetsakiris Closed Jan 27, 2026

Description

The Cowork tab in Claude Desktop App (v1.1.381) is stuck on "Sending request..." and eventually shows "API Error: Connection error". The Chat tab works fine, as does claude.ai in browser and Claude Code CLI.

This was working approximately one week ago.

Environment

App Version: 1.1.381
Platform: macOS Darwin 25.1.0 (Apple Silicon arm64)
Claude Code CLI: 2.1.15 (works fine)

Error Logs

From ~/Library/Logs/Claude/claude.ai-web.log:

[REACT_QUERY_CLIENT] QueryClient error: Error: path.conversation_uuid: Input should be a valid UUID, invalid character: expected an optional prefix of `urn:uuid:` followed by [0-9a-fA-F-], found `l` at 1

Refused to connect to 'https://a-api.anthropic.com/v1/m' because it violates the following Content Security Policy directive

[REACT_QUERY_CLIENT] QueryClient error: Error: Invalid authorization

Steps to Reproduce

Open Claude Desktop App
Go to Cowork tab
Send any message
Observe "Sending request..." that never completes, then "API Error: Connection error"

What Works

Chat tab in the same app ✅
claude.ai in browser ✅
Claude Code CLI ✅
VM starts and connects successfully ✅

Troubleshooting Attempted

Full app reinstall (deleted and re-downloaded)
Cleared all app data, cache, preferences, keychain
Verified network connectivity to api.anthropic.com (works)
Verified Anthropic status page shows all systems operational

Analysis

The error suggests the Cowork feature is passing local session IDs (prefixed with "local_") where the backend expects a proper UUID.

View original on GitHub ↗

16 Comments

benoj · 5 months ago

also seeing this

runninghare · 5 months ago

Me too. What's even stranger is that whenever the Claude App Cowork hangs, it also blocks my Claude Code. I have to clear my firewall rules again to make it work.

goslingmanagment · 5 months ago

Same on Claude 1.1.381

pandeptwidyaop · 5 months ago

Me too

MarshallOfSound · 5 months ago

@terencetsakiris can you use the "Send feedback" bug button in the bottom left of Claude desktop and make sure you attach your logs. Include this GitHub issue URL in your feedback text somewhere so I can find it easily 🙇 Will take a look once it comes in.

Can you also confirm here or in the feedback whether you have any special network configuration on your machine, proxies, vpns, etc.

kalabar794 · 5 months ago

Claude Cowork Error - "API Error: Connection error."
on Claude 1.1.799 (2e02b6) 2026-01-23T19:08:29.000Z

I was working fine for a couple of days and now it's broken. I turned off NextDNS, cleared Claude caches and reinstalled the Claude Desktop app. No luck.

Submitted bug with logs to Anthropic.

hershey-g · 5 months ago

same here

odoremieux · 5 months ago

Same with 1.1.886

robotcaptain · 5 months ago

Same issue here with 1.1.886

EcomGraduates · 5 months ago

same issue and I uninstalled and reinstalled but it never seems to send

mischasigtermans · 5 months ago

Same.

EMTurano · 5 months ago

@MarshallOfSound submitted bug with logs.

devli13 · 5 months ago

Having same issue on latest claude version, been stuck like this for nearly a week now and just discovered this thread.

MarshallOfSound · 5 months ago

Hey folks, as mentioned earlier, please submit feedback for this issue with logs so we can diagnose it further. Please reference this issue directly in your feedback so I can find it easily 🙇

MarshallOfSound · 5 months ago

Merging into #18006 as the same issue

github-actions[bot] · 5 months ago

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.