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I have a internet connection with live ip. I have forwarded routers port 21 to my local server, where I have installed FileZilla FTP server. It works fine in local environment, but when I try to access it with my public IP it returns error: 421 Login incorrect. It`s not showing the username/password popup, but directly prompts the error message.


  1. I can access my router with my public IP.
  2. I also have double checked whether my port is forwarded or not with this link.

What should I do next?

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I don't know if it is your problem, but you will also need to forward TCP port 20 ("ftp-data"). – Michael Kjörling Jul 27 '12 at 9:51
Thanks for the comment. I`ve forwarded the port 20, but still same result. – user144565 Jul 27 '12 at 10:32
@Community What the heck? this question is for 2012. please dont bring up such questions. thanks for attention. – TechLife Mar 30 '15 at 16:32

It can be that your server is set for PASV FTP mode, if true then you need to open the range of posts in your router selected in the server for passive mode.

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PASV FTP mode starts by initiating a connection on port 21 of the server and then the client will ask the server for another designated port to use, if that port is not open in your router then the connection will fail.
That can explain why you do not get a username:password prompt and it fails automatically.

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