Device.Net VS FluentFTP

This one was also a promising alternative at first since it markets itself as cross-platform, but apparently it still isn't. :P https://github.com/MelbourneDeveloper/Device.Net

Relevant XKCD

There are also various nuget packages about that can provide USB / Serial Port functionality, such as https://github.com/MelbourneDeveloper/Device.Net

I am using fluent ftp robinrodricks/FluentFTP which is a great library for downloading from ftp sites.

give FluentFTP a try, it's well documented and easy to use.

The PSFTP module is dependent upon System.Net.FtpWebRequest underneath. I believe this has some issues but, unfortunately, is also no longer under any development by MS. I believe they acknowledge there are known bugs for certain scenarios so it may not work but won’t be fixed. I believe that official recommendation is to look for a third-party alternative library! Consider https://github.com/robinrodricks/FluentFTP I believe that is a highly recommended library. Of course this is not a wrapped up PowerShell module like PSFTP, per se, but if you look in the Powershell folder of the git you will find example of usages. Also see here https://github.com/robinrodricks/FluentFTP/issues/434 the library can be used from PowerShell. Likely there are other alternatives too, but fundamentally you probably cannot use the native .Net Framework dependency. I believe newer .Net has superseded all this with entirely different API but that is likely not suitable for your current usage hence the third-party alternative as a recommendation.

Edit: looks like this is supported already https://github.com/robinrodricks/FluentFTP/wiki/File-Transfer so just kill the connection to pause presumably. Call UploadFile or DownLoadFile with existsMode set to append. This will automatically start where it left off.