FTPS upload loop

I have an issue that seems related to this bug, except that it doesn't have to be a large file, the transfer just has to take a while. I can reproduce this with a 248MB file uploading at 128KB/sec to make it last about 30 minutes, although I did notice this issue at first when transferring large (3 to 4GB) files that also take about 30 minutes to complete per file at full speed.

It is basically the same problem as what this post describes. Once the file has been transferred fully, WinSCP simply starts uploading the file again, and will do this over and over.

But, the catch is that it has to take a good while to transfer, like for example 30 minutes, or the bug will not occur. If completion time is rather short (like 10 minutes or something) then the bug does not occur for some reason.

As a workaround I currently have to babysit WinSCP until the file has about 30 seconds remaining, then I cancel the queue (so the queue gets emptied), then I add the file again and when it prompts me to overwrite the file, I select to resume the file and then when it completes it will behave normally and stop. If I try to pause instead of cancelling the queue, and then unpause, the same issue will occur, it seems I *have* to empty the queue.

As a test I have reproduced this issue by uploading a 248MB file with the speed limited at 128KB/sec and have created a log (invalid link removed by Admin) of level "Debug 2".

Thanks for your report.
I have sent you an email with a debug version of WinSCP to the address you have used to register on this forum.

It seems the email provider I used to register doesn't let your email come through. I have updated my address to another that should hopefully work better. Can you please resend the email to the new address? Thanks.

OK, sent again.

Thank you, this time I have received the email (the other address still has not received it, oh well...).

I have attached a 7z file as it compressed better than zip, and it stayed under the 10MB limit.

Can you try to set longer Server response timeout?
https://winscp.net/eng/docs/ui_login_connection

This did not work. I have tried both 60 and 120 seconds. Both times WinSCP would just sit there waiting with the time remaining 0:00:0 and 99% progress until the server response timeout is over, and then restarts uploading the file again.

Can you try even longer timeout? Do you have an access to server-side logs?