Register Winscp assembly for SFTP upload

Hi,
I am using WinSCP for an upload operation from powershell. I believe, to use the WinSCP assembly I have to register it in the system. So I copied Winscp.dll to C:\ and running the following command in command prompt:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\RegAsm.exe C:\WinSCP.dll /codebase /tlb

But, it's failing and returning error:
------
Microsoft (R) .NET Framework Assembly Registration Utility 4.0.30319.1
Copyright (C) Microsoft Corporation 1998-2004.  All rights reserved.

RegAsm : error RA0000 : Could not load file or assembly 'file:///C:\WinSCP.dll'
or one of its dependencies. Operation is not supported. (Exception from HRESULT:
 0x80131515)
------

Can anyone please help, how to fix this error?

Powershell Code i am going to use:
------------------
try
{
    # Load WinSCP .NET assembly
    [Reflection.Assembly]::LoadFrom("WinSCP.dll") | Out-Null
 
    # Setup session options
    $sessionOptions = New-Object WinSCP.SessionOptions
    $sessionOptions.Protocol = [WinSCP.Protocol]::Sftp
    $sessionOptions.HostName = "example.com"
    $sessionOptions.UserName = "user"
    $sessionOptions.Password = "mypassword"
    $sessionOptions.SshHostKeyFingerprint = "ssh-rsa 1024 xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx"
 
    $session = New-Object WinSCP.Session
 
    try
    {
        # Connect
        $session.Open($sessionOptions)
 
        # Upload files
        $transferOptions = New-Object WinSCP.TransferOptions
        $transferOptions.TransferMode = [WinSCP.TransferMode]::Binary
 
        $transferResult = $session.PutFiles("b:\toupload\*", "./", $FALSE, $transferOptions)
 
        # Throw on any error
        $transferResult.Check()
 
        # Print results
        foreach ($transfer in $transferResult.Transfers)
        {
            Write-Host ("Upload of {0} succeeded" -f $transfer.FileName)
        }
    }
    finally
    {
        # Disconnect, clean up
        $session.Dispose()
    }
 
    exit 0
}
catch [Exception]
{
    Write-Host $_.Exception.Message
    exit 1
}

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