Thanks for your report. So can you please try to identify the version that introduced the problem?
You can download all versions of WinSCP from:
The last version that worked correctly (allowed you to reload text file [ie. refresh the view when open] multiple times without it deleting lines from the file permanently) was 5.9.6.
In 5.10 beta it would allow one reload of text file, then on subsequent reload of file while file was still open, WinSPC would hang. I exited WinSPC by killing the process, re-entered WinSPC, and once I signed in to the remote server the text file that I was using to test with (which was being occasionally written to by "nohup php <php_script>.php > output.txt &") had less lines then when I first opened it before the program hung.
The same behavior happened in 5.10.1 beta, and in 5.10.2 beta WinSPC no longer hung after more than one reload of the text file, but after multiple reloads of the file being written to by "nohup php <php_script>.php > output.txt &", it deleted lines from the file.
I tested in 5.11 and it had the same behavior as 5.10.2 beta. This seems to be the same behavior afterwards upto the current version (although I have only tested the versions listed in this thread - it is only an assumption).
I hope that helps out.