claude-code - 💡(How to fix) Fix [BUG] Claude Desktop SSH: "Host denied (verification failed)" on Windows — VM never starts (isGuestConnected: false) [1 comments, 2 participants]

2026-04-16 [warn] Host <REMOTE_IP>:<CUSTOM_PORT> is not in known_hosts 2026-04-16 [error] Connection error: Host denied (verification failed) 2026-04-16 [error] Connection failed: Host denied (verification failed)

vm-info.json: "isGuestConnected": false (at every launch)

TL;DR

The SSH connection issue in Claude Desktop on Windows may be resolved by ensuring the known_hosts file is correctly formatted and accessible, or by adjusting the KEX algorithms to match the server's restrictions.

Guidance

• Verify that the known_hosts file is in the correct location and has the correct permissions, as the error message suggests it is being ignored.
• Check the KEX algorithms restricted on the server and ensure they match the algorithms supported by Claude Desktop, as a mismatch could cause the connection to fail.
• Review the ssh.log and cowork_vm_node.log files for any additional error messages or clues that could help diagnose the issue.
• Consider testing the SSH connection with a different set of KEX algorithms or a different known_hosts file to isolate the cause of the problem.

Example

No code snippet is provided as the issue is related to configuration and logging rather than code.

Notes

The issue may be related to the specific configuration of the SSH server or the Claude Desktop application, and further debugging may be required to determine the root cause. The fact that direct SSH from PowerShell works perfectly with the same credentials suggests that the issue is specific to Claude Desktop.

Recommendation

Apply workaround: Adjust the KEX algorithms to match the server's restrictions, as this is a potential cause of the issue and can be easily tested.