425 Can't Open Data Connection

Need help with FileZilla Server? Something does not work as expected? In this forum you may find an answer.

Moderator: Project members

Message
Author
mossy
500 Command not understood
Posts: 1
Joined: 2017-02-24 05:30
First name: Stephen
Last name: Moss

Re: 425 Can't Open Data Connection

#31 Post by mossy » 2017-02-24 05:35

Oh boy, boco is right, I ran thru the entire thread just to realize.... Don't use Windows FTP.exe. Most modern servers setup with mild security will block it's outdated methods.

Thanks guys.

mossy

taz1004
500 Command not understood
Posts: 1
Joined: 2017-05-22 20:26
First name: Brian
Last name: Choi

Re: 425 Can't Open Data Connection

#32 Post by taz1004 » 2017-05-22 20:34

Something is wacky. I just replaced my FTP server and copied the setting exactly and started getting this error. And I checked that everything on this thread and I was still getting the error. So I decided to turn off FTP over TLS by checking off Enable FTP over TLS support. And checked off Use custom port range in Passive mode settings. And External Server IP to Default. And it worked.
And then just to see which setting was causing the issue, I turned them back on one by one. First the FTP over TLS. It worked. Next, checked on Use custom port range. It worked again. Set external IP address back to what it was. Still working. So in the end, I just went back to how it was when it wasn't working. And now it works.

Don't understand this at all but just posting here as something else to try for those still having issue.

EDIT: Never mind, it stopped working again. Changing settings don't take effect immediately? It is definitely FTP over TLS causing this issue for me. I set everything that is suggested here. Maybe it's Windows 10 creators update?

User avatar
botg
Site Admin
Posts: 31065
Joined: 2004-02-23 20:49
First name: Tim
Last name: Kosse
Contact:

Re: 425 Can't Open Data Connection

#33 Post by botg » 2017-05-23 08:43

If it works without FTP over TLS but fails with it enabled you have a malicious firewall or NAT router tampering with the connection.

noelsantoro
500 Command not understood
Posts: 2
Joined: 2017-05-23 08:19

Re: 425 Can't Open Data Connection

#34 Post by noelsantoro » 2017-05-23 08:44

I've my FTP server on VM and I use pfsense firewall.

I can connect on my LAN Network but I can't outside.

I've tested with ftptest.net , and this is teh result :

....
Command: PBSZ 0
Reply: 200 PBSZ=0
Command: PROT P
Reply: 200 Protection level set to P
Command: PWD
Reply: 257 "/" is current directory.
Status: Current path is /
Command: TYPE I
Reply: 200 Type set to I
Command: PASV
Reply: 227 Entering Passive Mode (79,7,120,125,197,84)
Command: MLSD
Reply: 425 Can't open data connection for transfer of "/"
Error: Listing failed


so,.. I've set the passive port to 50000/51000
and 256*197+84 = 50516

I've set into firewall Rules and NAT :

WAN server adress 21 (FTP) FTP Service
WAN server adress 50000 - 51000 FTP Passive Mode
IPv4 TCP server adress 21 (FTP)
IPv4 TCP server adress 50000 - 51000

and also into Router Gateway I've set the Port Mapping TCP port 21

Any help , please ..

User avatar
botg
Site Admin
Posts: 31065
Joined: 2004-02-23 20:49
First name: Tim
Last name: Kosse
Contact:

Re: 425 Can't Open Data Connection

#35 Post by botg » 2017-05-23 09:28

What about the mapping for ports 50000 through 51000 in the gateway router?

noelsantoro
500 Command not understood
Posts: 2
Joined: 2017-05-23 08:19

Re: 425 Can't Open Data Connection

#36 Post by noelsantoro » 2017-05-23 09:50

I've tryed to mapping the port 50000/51000 on the Router Gateway setting ..
without change..

ElfoRojo
500 Command not understood
Posts: 1
Joined: 2018-05-16 16:59
First name: Jhon
Last name: Bedoya

Re: 425 Can't Open Data Connection

#37 Post by ElfoRojo » 2018-05-16 17:05

Hi all, am having this error trough a VPN Connection whit NAT, if i connect from the public IP (static) work fine, if i connect from internal IP works fine,
but when the people try to connect from a VPN whit NAT get the error 425 Can't Open Data Connection

the passive ports are open on both firewalls , the connection trough the 2222 port FTPS works but cant retrive the directories.

what can we do to solve this!

Post Reply