How To Setup L2TP PSK VPN on Windows

Open Network and Sharing Center, from the run box: control /name Microsoft.NetworkAndSharingCenter
Click Set up a new connection or network
Choose Connect to a workplace
If prompted to use a connection you already have, choose No, create a new connection
Choose Use my Internet connection (VPN)
Enter the IP address or hostname in the Internet address field
Enter a description in Destination name
After the new connection set up window closes, click on Change adapter settings
Right-click the new VPN connection and click on Properties
On the Security tab, choose the L2TP/IPSec option for Type of VPN
Click the Advanced settings button
Select Use preshared key for authentication and enter the PSK then click OK
Back on the Security tab, select Allow these protocols and then checkmark the MS-CHAP v2 option

Continuing from the steps above, go to the Networking tab and double-click the Internet Protocol Version 4 item
Click the Advanced button
Uncheck Use default gateway on remote network
On the DNS tab, enter the DNS suffix for this connection then click OK
Click OK two more times to save and close the new VPN connection
Open a PowerShell window and assign a route to the VPN connection for the remote network, example: Add-VpnConnectionRoute -ConnectionName "VPN Connection" -DestinationPrefix "10.10.0.0/16" -PassThru

REG ADD HKLM\SYSTEM\CurrentControlSet\Services\PolicyAgent /v AssumeUDPEncapsulationContextOnSendRule /t REG_DWORD /d 0x2 /f

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