Error 4

Hi.
When I try to upload stuff like .fxap, it does not only disapper from WinSCP but still in FileZilla, but also sometimes only upload some parts.
Ex. I installed Jobs Creator. Everything except from .fxap installed, and the Dev from the script says it can only be uploaded via WinSCP. So how do I get this script in my server, and when can I normally use WinSCP again? (I dont like FileZilla lol)