Authentication failures

Quick checklist

1. Username — is the profile’s username correct for this server?
2. Method — does the server allow the method you’re using? Many cloud images disable password login entirely; use a key instead.
3. Key — is the right private key selected, and does its public half exist in the server’s ~/.ssh/authorized_keys?
4. Passphrase — if the key has a passphrase, is the stored passphrase current?
5. Biometric prompt — a protected key requires Touch ID / Face ID at connect time; a cancelled prompt fails authentication.

Security keys

FIDO security keys fail in their own ways:

• You dismissed the system sheet — that counts as a failed authentication. The session parks and waits for you; it does not retry on its own.
• The server rejects the signature — check that it runs OpenSSH 8.2 or later, and that the sk-ecdsa-sha2-nistp256@openssh.com line really is in its ~/.ssh/authorized_keys.
• Require PIN is on but the server line has no verify-required — copy the public key again from the key library and replace the line on the server; the option is part of the copied text.
• The key isn’t there — a FIDO key can only sign while its hardware is plugged in or held to the device. Nothing is cached, on any device.

Host key errors are different

If the connection is blocked before a password/key prompt, that’s host key verification protecting you — the server’s fingerprint changed. Verify with the server admin before trusting the new key.

Still stuck?

Contact support with the exact error message shown.