Filezilla Connection error with windows 8.1

Whenever I am trying to connect with my web server with windows 8.1 then filezilla showing this error message as,

Status: Resolving address of anonymus.com

Status: Connecting to ...:21...

Status: Connection established, waiting for welcome message...

Response: 220 Welcome to Pure-FTPd [privsep][TLS]

Response: 220-You are user number 5 of 150 allowed.

Response: 220-Local time is now 04:50. Server port: 21.

Response: 220-This is a private system - No anonymous login

Response: 220-IPv6 connections are also welcome on this server.

Response: 220 You will be disconnected after 5 minutes of inactivity.

Command: USER user@user.com Response: 421 Sorry, cleartext sessions are not accepted on this server.

Error: Could not connect to server

but this is working with other windows please help me to resolve this.