Read and write from a remote PC to a shared powershell

This is my code

Write-Host "Remote copy a file" 
$username = 'Usuario' 
$password = 'Password' 

$myfile = [System.IO.File]::ReadAllBytes("C:\user.txt") ;
$Escribir={[System.IO.File]::WriteAllBytes("\192.x.x.x\foreach.txt", $args)} ;
$pw = ConvertTo-SecureString $password -AsPlainText -Force 
$cred = New-Object Management.Automation.PSCredential ($username, $pw) 
$servers = Get-Content C:\Users\Agent\Desktop\pcs
foreach($server in $servers) { 
$s = New-PSSession -computerName $server -credential $cred 
Write-Host "PC name: $server ..." -ForegroundColor GREEN -Background BLACK

$Job = Invoke-Command -Session $s -ArgumentList $myfile -ScriptBlock $Escribir -AsJob
    $Null = Wait-Job -Job $Job

Write-Host "Completed" 
Remove-PSSession -Session $s 
} 

I get the following error. If someone could help me to correct the error it would be great. Thanks.