How to Set Up a VPN on Windows XP | L2TP/IPsec

To add a necessary registry setting

1. In the Start menu search box, type “regedit” and press ENTER. You will be prompted to allow Administrator rights, click Yes.
2. Locate and click the registry subkey named HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\PolicyAgent
3. On the Edit menu, point to New, and click DWORD Value
4. In the New Value #1 box, type “AssumeUDPEncapsulationContextOnSendRule” (this is case-sensitive and contains no spaces), and press ENTER.
5. Right-click AssumeUDPEncapsulationContextOnSendRule, and select Modify.
6. In the Value data box, type “2” and click OK
7. Reboot the computer

How to install the certificate

1. Download the certificate from your vpn VPN provider and save it.
2. Open the Certificates Management Console
   . In the Start menu search box, type “mmc” and press enter.
   . You will be prompted to allow Administrator rights, click Yes.
   . From the File menu, select Add/Remove Snap-in…
   . In the Available snap-ins: list, double-click Certificates.
   . In the popup window, select Computer account, click Next, then click Finished.
   . Press OK to close the Snap-ins window.
3. Import the Certificate
   . In the center window, double-click Certificates (Local Computer), and then double-click Personal.
   . Right-click in the window, then go to All Tasks, then click Import…
   . Click Next, then Browse…, and locate the .p12 file you downloaded earlier.
   . Click Next, type the Password field and click Next again
   . Select Automatically select the certificate store based on the type of certificate and click Next, then click Finish

How to Configure

1. Open Network and Sharing Center in the Control Panel
   . Go to the Windows Menu, then Control Panel
   . Click on Network and Internet
   . Click on Network and Sharing Center
2. Click Setup a new connection or network
3. Choose Connect to a workplace then Next
4. Click Use my Internet Connection (VPN)
5. In the Internet address field, type the VPN server (get it from your VPN provider account)
6. In the Destination name field, type a descriptive name.
7. Check Don’t connect now then click Next
8. Type in your VPN Login and Password in their respective fields; leave Domain blank
9. Check Remember this password
10. Click Create and then Close
11. Open VPN Connection Properties
    . In Network and Sharing Center, click Change adapter settings
    . Right-click your new connection and click Properties
12. Configure for L2TP/IPsec
    . On the Security tab, change the dropdown box from Automatic to Layer 2 Tunneling Protocol with IPsec (L2TP/IPsec)
    . Click Advanced and confirm that both the Use certificate for authentication and Verify the Name and Usage attributes of the server’s certificate are selected
    . On the security tab, change the Data Encryption to Maximum strength encryption to enable 256-bit encryption.

How to Connect

1. In the Windows Taskbar, click on the Network icon
2. Click on your new connection, and then click on the Connect button
3. Type in your VPN Login and Password in their respective fields and click Connect

How to Disconnect

1. Click the Network icon on the taskbar
2. Click the name of your VPN connection, then Disconnect