File transferred by FTP over HTTP proxy, file on server present but only content is HTTP header text

Hello,

First thanks for WinSCP and this support forum. In regard to issue we're experiencing...

WinSCP 5.7.6
Local OS is Windows 7
File protocol = FTP, no encryption
HTTP proxy employed
All other configs are WinSCP default

Receiving server spec - Serv-U 14.0.1.0 on Windows Server 2008

Issue we are experiencing is that for approximately 1 out of 4 files transmitted, the file received on the server side does not contain the data in the file transmitted from the client side. Instead, a file is created that merely contains what appears to be HTTP header text. Below is an example:

[example start]
GET / HTTP/1.1
Accept: */*
Accept-language: en, *;q=0.7
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; InfoPath.1; .NET CLR 2.0.50727; .NET CLR 1.1.4322; MS-RTC LM 8; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)
Host: XX.XXX.XX.XX
Connection: Keep-Alive
[example end]

Attached is a segment from server log where we captured the issue. 7 test files transmitted in succession, no variation in user action. All files identical, only different is file names. File '*test4' produced the issue, no others did.

Would be grateful for any suggestions on how to prevent this issue.

Did you try another FTP client?

Yes, just after making the initial post I did 10 test files with FileZilla and 3 of the files produced the error.

Any thoughts on whether this is an issue with the proxy or the receiving FTP server? And could there be a WinSCP configuration that would prevent it?

Thanks again!

Correction: My earlier response was incorrect - I was looking at a second series of transfers with WinSCP. FileZilla has not reproduced the error. I just ran 20 files with each, WinSCP and FileZilla. WinSCP had the error in 13 of the files, sporadically occurring (at least it seems sporadic). FileZilla didn't produce any of the error files containing an HTTP string.

Thanks for the additional details.

Can I have a test account on your server?
Can you attach WinSCP and FileZilla verbose logs?

martin wrote:

Thanks for the additional details.

Can I have a test account on your server?
Can you attach WinSCP and FileZilla verbose logs?

Im experiencing the exact same problem. Any updates on the solution or possible cause?

Casperonian wrote:

Im experiencing the exact same problem. Any updates on the solution or possible cause?

Then I need exactly the same information that I've asked for above.

martin wrote:

Casperonian wrote:

Im experiencing the exact same problem. Any updates on the solution or possible cause?

Then I need exactly the same information that I've asked for above.

How do I activate the logs? I am using the WinSCPnet.dll to develop the solution.

How do I activate the logs? I am using the WinSCPnet.dll to develop the solution.

Use Session.SessionLogPath. And I also need verbose FileZilla log files.