Re: Reply
You should use generate a script, not a URL:
https://winscp.net/eng/docs/ui_generateurl#script
https://winscp.net/eng/docs/ui_generateurl#script
Before posting, please read how to report bug or request support effectively.
Bug reports without an attached log file are usually useless.
So can the vendor connect to the server anyhow? In WinSCP GUI? Using any other FTP client? Can the vendor even ping the server?