425 Can't open data connection for transfer of “/”
The router mapping seems suspicious, as you have correctly guessed. It looks like you have all public ports in range 51000-61000 mapped to a single internal port 51000. What would explain, why the client is not able to connect to port 52573.
If your router is not able to map a range of internal ports, you can configure your FTP server to use only a narrow range (like 51000-51010) and configure those ports one-by-one.
See also How many data channel ports do I need for an FTPS server running behind NAT?
Related videos on Youtube
Raikoug
Updated on September 18, 2022Comments
-
Raikoug over 1 year
I'm trying to solve this error searching the web, without any success.
The error is:
425 Can't open data connection for transfer of "/"
My software:
- Windows server 2013 and last filezilla server
My topology:
- Server wired to router - Router with a dynamic IP from ISP, dynamic dns updated.
My settings:
- PASV mode with ports 51000-61000
- Retrieve external ip with http://ip.filezilla-project.org/ip.php
- Enabled FTP over TLS with port 990
Where I opened my ports
- router: local and public 21, local 51000 public 51000-61000, local and public 990 (ALL tcp)
- Windows Firewall: both directions, ports 21, 51000-61000, 990.
On my lan it works perfectly. I think there's something wrong with router port forwarding configuration. Here it is.
My port forwarding configuration on router
Is there something I'm doing wrong?
I add a log of my ftp server:
(000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> PBSZ 0 (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> 200 PBSZ=0 (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> PROT P (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> 200 Protection level set to P (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> PWD (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> 257 "/" is current directory. (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> TYPE I (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> 200 Type set to I (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> PASV (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> 227 Entering Passive Mode (my,ip,addr,ess,205,93) (000013)06/11/2017 21:50:57 - user (my.ip.add.ress)> MLSD (000013)06/11/2017 21:51:07 - user (my.ip.add.ress)> 425 Can't open data connection for transfer of "/"
I add the ftp server configuration screens too just in case.
-
Martin Prikryl over 6 yearsWhat is the error from client-side? What client are you using? Does the
my,ip,addr,ess
in the227
response match the IP that the client is connecting to? -
Raikoug over 6 yearsRemote client and server have the same error. my,ip,addr,ess is the correct one.
-
Martin Prikryl over 6 yearsWell, the router mapping seems suspicious, as you have correctly guessed. It looks like you have all public ports in range 51000-61000 mapped to a single internal port 51000. What would explain, why the client is not able to connect to port 52573.
-
Raikoug over 6 yearsWell I guess I have few choices: 1) Change router (very hard one, since is ISP provided). --- 2) I have a DMZ option to bypass any port forwarding to my server. Very dangerous I think. --- 3) SFTP, I think all trafic just pass from port 22 or the custom 1 i chose..
-
Martin Prikryl over 6 yearsIf your router is not able to map a range of internal ports, you can configure your FTP server to use only a narrow range (like 51000-51010) and configure those ports one-by-one.