FTPS certificate error
Why FTPS certificate validation fails and how to fix expired or mismatched certificates.
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Certificate errors occur when the FTPS client cannot validate the server certificate.
Common causes
- Expired certificate
- Self-signed certificate
- Hostname mismatch
- Missing CA trust chain
Fix checklist
- Renew expired certificates.
- Ensure hostname matches certificate CN.
- Install proper CA certificates.
- Configure client to trust the certificate if appropriate.
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