FTPMonitor / Guides / FTPS certificate error

FTPS certificate error

Why FTPS certificate validation fails and how to fix expired or mismatched certificates.

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

Certificate errors occur when the FTPS client cannot validate the server certificate.

Common causes

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