Opened 15 years ago

Closed 11 years ago

Last modified 10 years ago

#3823 closed Bug report (outdated)

SFTP consistently get "Server unexpectedly closed network connection" upon connecting

Reported by: Brad Owned by:
Priority: normal Component: FileZilla Client
Keywords: Cc:
Component version: Operating system type: Windows
Operating system version: xpsp3


PSFTP works fine, and Filezilla works *sometimes* but not often. Have firewall between client/server, cannot turn off... but since it works sometime, assume firewall not the issue. When I turn on debug mode, get following trace:

Status: Connecting to
Trace: Going to execute "C:\Program Files\FileZilla FTP Client\fzsftp.exe"
Response: fzSftp started
Trace: CSftpControlSocket::ConnectParseResponse(fzSftp started)
Trace: CSftpControlSocket::SendNextCommand()
Trace: CSftpControlSocket::ConnectSend()
Command: open "birthb@…" 22
Trace: Looking up host ""
Trace: Connecting to port 22
Trace: Server version: SSH-2.0-Serv-U_7.2.0.1
Trace: Using SSH protocol version 2
Trace: We claim version: SSH-2.0-PuTTY_Local:_Sep_29_2008_13:48:04
Trace: Using Diffie-Hellman with standard group "group1"
Trace: Doing Diffie-Hellman key exchange with hash SHA-1
Trace: Server unexpectedly closed network connection
Error: Server unexpectedly closed network connection
Trace: CSftpControlSocket::ResetOperation(66)
Trace: CControlSocket::ResetOperation(66)
Error: Could not connect to server

Change History (2)

comment:1 by Tim Kosse, 15 years ago

Status: newmoreinfo

The SFTP support in FileZilla is based upon PuTTY's psftp component.

Can you successfully connect to the server using psftp? (

comment:2 by Alexander Schuch, 11 years ago

Resolution: outdated
Status: moreinfoclosed

No reply for more than 28 days.

Chances are that the issue was solved already due to newer releases of upstream psftp and FileZilla itself.

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