Hello, 
I am pretty new in WinSCP/PowerShell.
Im trying to connect to a FTP server using 
SshHostKeyFingerprint, all parameters are correct because I copied paste from a working WinSCP script.
But when I am trying a very basic 
$session.open, I'm getting the error message 
    Exception calling "Open" with "1" argument(s): "Host "....com" does not exist.    
Not sure the problem comes from the hostname
Could you please help?
My script:
    function test_connect{
    try {
        # Load WinSCP .NET assembly
        Add-Type -Path ".\WinSCP-5.17.10-Automation\WinSCPnet.dll"
 
        # Setup session options
        $sessionOptions = New-Object WinSCP.SessionOptions
        $sessionOptions.Protocol = [WinSCP.Protocol]::Sftp
        $sessionOptions.HostName = "sftp://xxxx@yyyyyyyy.com/"
        $sessionOptions.SshHostKeyFingerprint = "ssh-ed25519 256 3D....="        
   
        $session = New-Object WinSCP.Session
        try {
            # Connect
            $session.Open($sessionOptions)
        }
        finally {
            # Disconnect, clean up
            $session.Dispose()
        }
 
        # exit 0
    }
    catch {
        Write-Host "Error: $($_.Exception.Message)"
        # exit 1
    }
}