[BUG] [Bug] SSH connection fails on Windows: "Failed to spawn /usr/bin/ssh: spawn /usr/bin/ssh ENOENT"

Found 1 possible duplicate issue:

1. https://github.com/anthropics/claude-code/issues/25659

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This will be fixed in the next release.

It seems the issue was indeed fixed in the latest release, but only partially: the windows desktop app still does not use the same ssh that I have set up in the command line, and ignores my PKCS11 key (Yubico). Here is the relevant part of the ssh.log:

2026-02-17 21:30:41 [info] [RemoteServerController] Ensuring server is ready on *** (trigger: send_message)
2026-02-17 21:30:41 [info] [BinaryDeployment] Setting up remote server on ***
2026-02-17 21:30:41 [info] [SSH2Connection] Resolved *** -> ***@***:***
2026-02-17 21:30:41 [info] [SSH2Connection] Connecting to ***@***:*** (agent: false, key: true, proxy: false, keyboard: true)
2026-02-17 21:30:42 [error] [SSH2Connection] Connection error: All configured authentication methods failed
2026-02-17 21:30:43 [info] [SSH2Connection] Retrying with password auth (keyboard-interactive not available)
2026-02-17 21:30:45 [error] [SSH2Connection] Connection error: All configured authentication methods failed
2026-02-17 21:30:45 [error] [RemoteServerController] Connection failed (3814ms, trigger: send_message): All configured authentication methods failed

I also note that the logs show agent: false despite ssh agent running (ssh-add -L shows keys).

It still doesn't work in Version 1.1.3541 (1e65e4) on Windows 11 Pro. I get this error:

Binary not found: C:\Program Files\WindowsApps\Claude_1.1.3541.0_x64__pzs8sxrjxfjjc\app\resources\claude-ssh\claude-ssh-linux-amd64 Try again

I also tried reinstalling it, but it didn't help either.

Strange Cannot parse privateKey: Encrypted private OpenSSH key detected, but no passphrase given Try again error happens, regardless of what I tried

2026-02-19 xxxxxxx [info] [EventLogging] Queuing event: desktop_ssh_connection_failed | metadata: {
  product_surface: 'claude-desktop',
  app_version: '1.1.3541',
  commit_hash: '1e65e4f0a2acc921b2009fc1216fc2b78cd93d18',
  platform: 'win32',
  arch: 'x64',
  error_message: 'Cannot parse privateKey: Encrypted private OpenSSH key detected, but no passphrase given',
  trigger: 'send_message'
}

I tried with/without passphrase. Does this come from a similar error, or should i open up a new issue?

Workaround that worked on Windows 11

After debugging the SSH log at %APPDATA%\Claude\logs\ssh.log, I found two root causes and a reliable workaround.

What the log revealed

[SSH2Connection] Connecting to user@host:22 (agent: none, keys: 1[ssh-ed25519], ...)
[SSH2Connection] ssh2: Client: publickey auth failed
[SSH2Connection] Connection error: All configured authentication methods failed

The Desktop app's internal ssh2 library (not the system SSH):

1. Cannot load RSA private keys — even after converting from OpenSSH format (-----BEGIN OPENSSH PRIVATE KEY-----) to PEM format (-----BEGIN RSA PRIVATE KEY-----), the key is silently skipped
2. Ignores IdentityFile and IdentitiesOnly yes in ~/.ssh/config — it always falls back to trying the default ~/.ssh/id_ed25519
3. Requires forward-slash paths — IdentityFile C:\Users\...\id_rsa is not parsed correctly; use ~/.ssh/keyname instead

Fix

The app will always send ~/.ssh/id_ed25519 regardless of SSH config. So the workaround is:

1. Make sure you have an ed25519 key at ~/.ssh/id_ed25519 (generate one if needed: ssh-keygen -t ed25519 -f ~/.ssh/id_ed25519)
2. Add its public key to the server's authorized_keys for the target user:

``
ssh-copy-id -i ~/.ssh/id_ed25519.pub user@yourserver
``

1. In ~/.ssh/config, use forward-slash paths:

``
Host myserver
HostName your.server.ip
User youruser
Port 22
IdentityFile ~/.ssh/id_ed25519
``

Once the server accepts ~/.ssh/id_ed25519, Claude Desktop connects without issues. The IdentityFile line in the config doesn't matter for which key gets sent, but keeping it clean helps readability.

Environment

• Windows 11 Pro 10.0.26200
• Claude Desktop (latest)