[BUG] Cowork Windows - API Error: Unable to connect to API (ECONNRESET)

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?

After installing the latest Claude Desktop for Windows with Cowork,
every task I attempt fails with the following error:

"API Error: Unable to connect to API (ECONNRESET)"

Cowork works partially — the tab appears, tasks start, and the VM
runs for several minutes showing "Trabajando en ello..." before
failing with the error above. Even simple tasks like creating a
text file fail consistently.

What Should Happen?

Cowork should complete the task successfully.

Error Messages/Logs

"API Error: Unable to connect to API (ECONNRESET)"

Steps to Reproduce

1. Open Claude Desktop on Windows 11 Pro
2. Switch to Cowork tab
3. Enter any task (even simple ones like "create a text file")
4. Wait several minutes
5. Error appears: API Error: Unable to connect to API (ECONNRESET)

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

N/A

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

• Hyper-V was not enabled initially, was enabled before testing
• Fresh install of Claude Desktop from claude.com/download
• Pro plan subscriber