Unable to establish FTP connection to Plesk server: Insecure server, it does not support FTP over TLS

Alexander Davydov

Updated January 13, 2026 19:10

Plesk for Windows kb: technical

Applicable to:

Unable to establish FTP connection to Plesk server with the following error message:

CONFIG_TEXT: Insecure server, it does not support FTP over TLS

Misconfiguration of FTP SSL Settings for Plesk server IP address.

Connect to the server via RDP.
Open Internet Information Services (IIS) Manager at Start > Windows Administrative Tools page.
Go to server_name > Sites > 203.0.113.2 > FTP SSL Settings page.
In the drop-down menu select Plesk as SSL Certificate:
Press Apply to save changes.