FileZilla successfully connects but fails to upload

From FileZilla, I can successfully connect to my webserver but attempting to upload any file to any location fails. Here is the log of that process:

Status: Resolving address of mythofechelon.co.uk
Status: Connecting to 212.48.67.44:21...
Status: Connection established, waiting for welcome message...
Response: 220---------- Welcome to Pure-FTPd [privsep] [TLS] ----------
Response: 220-You are user number 1 of 50 allowed.
Response: 220-Local time is now 13:14. Server port: 21.
Response: 220-IPv6 connections are also welcome on this server.
Response: 220 You will be disconnected after 15 minutes of inactivity.
Command: USER ben
Response: 331 User ben OK. Password required
Command: PASS **********
Response: 230 OK. Current restricted directory is /
Command: SYST
Response: 215 UNIX Type: L8
Command: FEAT
Response: 211-Extensions supported:
Response: EPRT
Response: IDLE
Response: MDTM
Response: SIZE
Response: MFMT
Response: REST STREAM
Response: MLST type*;size*;sizd*;modify*;UNIX.mode*;UNIX.uid*;UNIX.gid*;unique*;
Response: MLSD
Response: AUTH TLS
Response: PBSZ
Response: PROT
Response: ESTA
Response: PASV
Response: EPSV
Response: SPSV
Response: ESTP
Response: 211 End.
Status: Server does not support non-ASCII characters.
Status: Connected
Status: Retrieving directory listing...
Command: PWD
Response: 257 "/" is your current location
Command: TYPE I
Response: 200 TYPE is now 8-bit binary
Command: PASV
Response: 227 Entering Passive Mode (212,48,67,44,171,207)
Command: MLSD
Response: 150 Accepted data connection
Response: 226-Options: -a -l
Response: 226 32 matches total
Status: Directory listing successful
Status: Retrieving directory listing...
Command: CWD public_html
Response: 250 OK. Current directory is /public_html
Command: PWD
Response: 257 "/public_html" is your current location
Command: PASV
Response: 227 Entering Passive Mode (212,48,67,44,54,40)
Command: MLSD
Response: 150 Accepted data connection
Response: 226-Options: -a -l
Response: 226 9 matches total
Status: Directory listing successful
Status: Resolving address of mythofechelon.co.uk
Status: Connecting to 212.48.67.44:21...
Status: Connection established, waiting for welcome message...
Response: 220---------- Welcome to Pure-FTPd [privsep] [TLS] ----------
Response: 220-You are user number 2 of 50 allowed.
Response: 220-Local time is now 13:14. Server port: 21.
Response: 220-IPv6 connections are also welcome on this server.
Response: 220 You will be disconnected after 15 minutes of inactivity.
Command: USER ben
Response: 331 User ben OK. Password required
Command: PASS **********
Response: 530 Login authentication failed
Error: Critical error
Error: Could not connect to server
Status: Delaying connection for 5 seconds due to previously failed connection attempt...

Original diagnostic results:

1. The same issue occurs using a fresh install of FileZilla 3.7.3 (the latest version)
2. The same issue occurs on multiple PCs
3. The same issue has occurred on multiple sites and, therefore, different internal networks
4. I can successfully upload via cPanel's File Manager

Edit:

New diagnostic results:

1. Changing FileZilla's transfer type to Auto, ASCII, or Binary doesn't make a difference
2. After the file transfer fails, disconnecting from the server and attempting to reconnect also fails. Quitting and re-launching FileZilla allows me to reconnect again
3. The same issue occurs on a freshly-installed Windows 7 x64 VM with a bridged network, no security software, and default Windows firewall rules
4. Using WinSCP (as suggested by Ryan) with the same credentials works

3 Answers

It appears your FTP account is limited to a single concurrent session. By default, FileZilla tries to transfer files in a separate FTP session so you can keep browsing in the primary session.

There are two possible fixes:

• Contact the FTP server operator and have them remove this ridiculous limit
• Set FileZilla to use only one connection: It will then perform transfers in the primary connection.

I faced the same problem, I solved this by clearing the Private Data:

Go into Edit --> Clear Private Data and check Quickconnect history, Reconnect information, Transfer queue. Then click OK.

I just had the same issue backing up my hosting server to my local hard drive. I went to bed with Filezilla running, and when I woke up it was still connected, but not transferring.

I don't know why this worked, but it did.

After tweaking a few things (not really knowing what I was doing), I clicked on "Toggles processing of the transfer que". This button on my version was directly underneath the menu item, "Server". As soon as I clicked on that button, everything started working again.

Hope this helps somebody.