- Plesk Onyx for Windows
- Plesk 11.x for Windows
- Plesk 12.0 for Windows
Cannot connect to FTP server using Filezilla, the following error is shown:
Response: 534-Protection level negotiation failed.
Response: Win32 error: Access is denied.
Response: Error details: Protection negotiation failed. PROT command with recognized parameter must precede this command.
Response: 534 End
Error: Failed to retrieve directory listing
Connections from other clients and from the server itself are possible.
FTP client expects the certificate or secure connection.
1. Allow custom FTP settings for IP addresses (
Tools & Settings > Security policy > Secure FTP - Use custom FTPS policy per IP address
2. Allow secured and non-secured FTP connection to this IP address ( Tools & Settings > IP addresses > ip_address > Allow both secure FTPS and non-secure FTP connections )