FTPS explicit vs implicit configuration
Understanding explicit vs implicit FTPS and why incorrect configuration causes connection failures.
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FTPS supports explicit and implicit encryption modes.
Clients must use the correct mode to connect successfully.
Common causes
- Client using implicit FTPS against explicit server
- Incorrect port (21 vs 990)
- TLS negotiation mismatch
Fix checklist
- Confirm server encryption mode.
- Use correct port (21 for explicit, 990 for implicit).
- Update client configuration.
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- FTP 530 Login incorrect — How to fix FTP 530 errors: bad credentials, account restrictions, FTPS requirements, and permission issues.
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