I have sent you a debug version, no response yet.

Thanks. I'll contact you if I need futher information to fix the problem.

Thank you for your reply.
Here is the part of the log that should be relevant.

. 2007-10-02 12:02:58.929 Sent 32768 bytes
. 2007-10-02 12:02:58.929 There are 35964 bytes remaining in the send buffer
. 2007-10-02 12:02:58.929 Looking for network events
. 2007-10-02 12:02:58.929 Detected network event
. 2007-10-02 12:02:58.929 Enumerating network events for socket 560
. 2007-10-02 12:02:58.929 Enumerated 3 network events for socket 560
. 2007-10-02 12:02:58.929 Detected network read event on socket 560 with error 0
. 2007-10-02 12:02:58.929 Received 28 bytes (0)
. 2007-10-02 12:02:58.929 Read 4 bytes (24 pending)
. 2007-10-02 12:02:58.929 Read 24 bytes (0 pending)
< 2007-10-02 12:02:58.929 Type: SSH_FXP_STATUS, Size: 24, Number: 11782
< 2007-10-02 12:02:58.929 65,00,00,2E,06,00,00,00,04,00,00,00,07,46,61,69,6C,75,72,65,00,00,00,00,
< 2007-10-02 12:02:58.929 Status/error code: 4, Message: 11782, Server: Failure, Language:
. 2007-10-02 12:02:58.929 Waiting for another 4 bytes
. 2007-10-02 12:02:58.929 Looking for incoming data
. 2007-10-02 12:02:58.929 Looking for network events
. 2007-10-02 12:02:59.054 Detected network event
. 2007-10-02 12:02:59.054 Enumerating network events for socket 560
. 2007-10-02 12:02:59.054 Enumerated 1 network events for socket 560
. 2007-10-02 12:02:59.054 Detected network read event on socket 560 with error 0
. 2007-10-02 12:02:59.054 Server sent command exit status 141
. 2007-10-02 12:02:59.054 All channels closed. Disconnecting
. 2007-10-02 12:02:59.054 Selecting events 0 for socket 560
. 2007-10-02 12:02:59.054 Server closed network connection
. 2007-10-02 12:02:59.054 Fatal error while disposing the SFTP queue.

So its the server who simply kills the connection. The question is whether this behaviour of winscp is by design.

Can you post a log file?

SRC is local machine
TGT is remote host

If I copy a file in binary mode from SRC to TGT via ssh that is too large
for the filesystem on TGT, winscp crashes with Windows
"Abnormal program termination"

Version is WinSCP version 404
SRC is Windows 2003 from a Terminal Server session
TGT is HPUX 11 PA_RISC 64bit.

Session details are:
Session protocol = SSH-2
SSH implementation = OpenSSH_3.9
Encryption algorithm = aes
Compression = No
File transfer protocol = SFTP-3
------------------------------------------------------------
Server host key fingerprint
ssh-rsa 1024 xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx
------------------------------------------------------------
Can change permissions = Yes
Can change owner/group = No
Can execute arbitrary command = No
Can create symlink/hardlink = Yes/No
Can lookup user groups = No
Can duplicate remote files = No
Can check available space = No
Can calculate file checksum = No
Native text (ASCII) mode transfers = No
------------------------------------------------------------
Additional information
The server does not support any SFTP extension.