File ccontents change once file has been uploaded

I have a file monitored for upload, but once in a while, when the file is uploaded and the contens of file is completely different. It looks like the original data is replaced by a log file generated by SmartFTP. I have been struggling with this issue for quite some time and I am tired of having to go and change my original file back to normal manually. I upload multiple files, but only one gets replaced by this unknown data and it is always the same one. Please help as I can provide more details.

Hello ..

This is almost impossible. The log is only in the memory of SmartFTP and not written to a physical file. Do you know how to reproduce the problem?

Also before you test it please install the latest version from:
https://www.smartftp.com/download

Regards,
Mat