Welcome to the forum @Eddy
I don’t know why Windows version makes a difference, except possibly for .NET Framework versions which seem to go up periodically (but Windows 7 also gets updated, I think). FTP, if that’s exactly the Storage Type you’re on, is .NET Framework. Have you tried using FTP (Alternative) instead of that? There’s an even newer version of that third-party FluentFTP client in the Beta that came out today…
There are also options on both clients that you can play with, and some debugtest tools if need be…