[BUG] Multiple Issues with Claude Cowork - Failed to start Claude's Workspace
Status Fixed / completed
Maintainer reply None cached
Activity 5 comments · opened Feb 24, 2026 · closed Feb 26, 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?
I am trying to use Claude cowork
Issue 1:
Failed to start Claude's workspace
Can't reach the Claude API from Claude's workspace.
I fixed the first issue but then I am getting the below issue.
Issue 2:
Filed to start Claude's workspace
failed to create network endpoint: HcnCreateEndpoint failed with HRESULT
0x800706bf
There are multiple issues popping up when I try to fix something.
What Should Happen?
Cowork should load without errors
Error Messages/Logs
Steps to Reproduce
- Login to Cowork
Claude Model
None
Is this a regression?
Yes, this worked in a previous version
Last Working Version
1.1.23
Claude Code Version
1.1.4088
Platform
Anthropic API
Operating System
Windows
Terminal/Shell
PowerShell
Additional Information
_No response_
5 Comments
Found 2 possible duplicate issues:
This issue will be automatically closed as a duplicate in 3 days.
🤖 Generated with Claude Code
Environment: Windows 10 Pro, Claude Desktop 1.1.4173, personal machine (no corporate MDM)
Symptoms experienced:
VM service disabled itself on install → fixed by re-enabling via PowerShell
WinNAT missing/corrupted → had to stop/start WinNAT service to recreate it
"Can't reach the Claude API from Claude's workspace" persisted even after NAT was working
Root cause identified via netstat:
The cowork-svc.exe process has zero listening ports. The MITM proxy component never binds to the 172.16.0.1 virtual adapter. The VM starts and connects successfully (guest connection confirmed in logs), but has nowhere to send API traffic.
The VM logs confirm this sequence:
[VM] API reachability: PROBABLY_UNREACHABLE
[VM] API reachability: UNREACHABLE
[VM:network] API is unreachable
Host connectivity is fine — Test-NetConnection api.anthropic.com -Port 443 succeeds from the host. The issue is the proxy not starting, not routing/NAT.
Debug logs submitted via the in-app link.
Bug seems to be fixed on Claude 1.1.4328 (d8e391). I am able to use Cowork without any issue
Hey folks, we just released v1.1.4328 which should fix all these networking issues
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.