FTPMonitor / Guides / FTP SSL negotiation failed

FTP SSL negotiation failed

Why FTPS SSL negotiation fails and how to fix TLS configuration issues.

Diagnose this automatically

Verify whether authentication is the actual failure point.

terminal

npx ftpmonitor check --protocol ftps --host ftps.example.com --port 21 --username user --password pass

Shareable output

terminal

npx ftpmonitor check --protocol ftps --host ftps.example.com --port 21 --username user --password pass --format slack --copy

SSL negotiation failures occur when a secure FTP connection cannot be established.

Common causes

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FTP server requires FTPS — Why plain FTP connections fail when a server requires FTPS encryption.
Authentication failed — Why FTP/SFTP authentication fails and how to correct credential, key, and account policy issues.
FTP 530 Login incorrect — How to fix FTP 530 errors: bad credentials, account restrictions, FTPS requirements, and permission issues.