README.md

A script to add a VPN connection in Windows 10

1. Download both of the scripts, and place both files on the desktop.
2. Double click on the VPN.bat file
3. When prompted click "Yes" to run the script as an administrative user
4. Enter the connection details when prompted (VPN address, pre shared key)
5. Reboot

VPN.bat

@ECHO OFF
PowerShell.exe -ExecutionPolicy Bypass -Command "& '~\Desktop\z-ms-l2tp-ipsec.ps1'"
PAUSE

z-ms-l2tp-ipsec.ps1

#> 
  <#
  .SYNOPSIS
    This script adds an L2TP over IPsec VPN while asking for name, gateway IP address, and pre shared key.
    Version: 1.0.4  
  .DESCRIPTION
    With this Powershell Script the addition of an L2TP over IPsec VPN can be automated
  #>
 
#checks if powershell is in Administrator mode, if not powershell will fix it  
if (-not ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")) {     
    $arguments = "& '" + $myinvocation.mycommand.definition + "'"  
    Start-Process powershell -Verb runAs -ArgumentList $arguments  
    Break  
}  
  
# General settings  
$VpnName = Read-host -Prompt "Whats the name of the VPN Connection?" 
$gateway = Read-Host -Prompt "Whats the gateway of the VPN Connection" 
write-host "$vpnname " -f yellow -NoNewline ; write-host "is the name of the connection and gateway" -NoNewline ; write-host " $gateway." -f Yellow  
$psk = Read-Host -Prompt "Enter preshared key for the VPN"  
$regp = 'HKLM:\SYSTEM\CurrentControlSet\Services\PolicyAgent' #if VPN server is behind NAT, otherwise comment out this line.  

# UDP encapsulation
REG ADD HKLM\SYSTEM\CurrentControlSet\Services\PolicyAgent /v AssumeUDPEncapsulationContextOnSendRule /t REG_DWORD /d 0x2 /f
  
# Add l2tp vpn  
Add-VpnConnection -Name $VpnName -ServerAddress $gateway -TunnelType L2tp -AuthenticationMethod MSChapv2 -EncryptionLevel Required -L2tpPsk $psk -Force ` 
-AllUserConnection -UseWinLogonCredential $false -SplitTunneling  
 
Write-Host "Connection has been added." -f Green  
 
# Add registry value, if VPN server is behind NAT. Otherwise comment out this line.  
New-ItemProperty -Path $regp -Name AssumeUDPEncapsulationContextOnSendRule -Value 2 -PropertyType 'DWORD' -Force  
  
$confirm = Read-Host -Prompt '... L2Tp over IPsec is added. System needs to be restarted before the VPN connection can work. Reboot system? Y/N ...'  
 
If (($confirm -eq "Y")) { 
    Restart-Computer 
}
else { 
    $cp = Read-Host -Prompt "Ok. Closing Powershell? Y/N" 
     
    if (($cp -eq "Y")) { 
        ncpa.cpl 
        Get-Process powershell | Stop-Process 
    }
    else { 
        ncpa.cpl 
    } 
}