Re-enable IPSec According to reports, the VPN error 789 can happen on your Windows 7/8/10/11 PC if you disable essential services for self-hosted VPNs. To fix the error, re-enable them.
VPN returns error 789. Solved! You will see a very good 789 error if your system has not been properly configured to connect to a very good L2TP server. The attempt failed before you can connect to the host server. This is also due to the bad configuration of your driving system.
The following procedure resolves error: 789 when configuring L2TP over IPsec on Windows 10. “Error: 789, The L2TP connection attempt failed because the security layer encountered a processing error during initialization negotiation with its counterpart” 1. Open Administration via Control Panel.
After upgrading to Windows 11, the Always On VPN connection may fail with the following error message. “A virtual access connection was established, but authentication failed because the certificate the client often uses to authenticate with the server is not valid. Verify that the certificate used for authentication is valid.”
In the meantime, we encourage you to review these steps. Click the Start button, then Settings > System > click Troubleshoot > click Other Troubleshooters and click Network Troubleshooter.
You can read about error 789 and details that “The L2TP connection attempt failed because the security layer encountered a processing error during initial negotiation with a normally remote computer.” On Windows 10/11, whenever you try to connect to a VPN, you see a screen in the bottom right corner of the screen.
Is there an error code for VPN error 789?
Quite often, internet users will encounter various conditions when trying to use this stable connection, and no matter which learning system you use, there should be a high chance of encountering a number of VPN error codes. Today’s discovery error is VPN error 789.
How do I fix Error 800 789 L2TP and setup VPN in Windows 7?
Fixed: Error 700 Windows 7 (L2TP client over Sec-IP cannot connect)
- In Windows 7, go to VPN connection properties and click “Security”.
- Select L2TP/IPSec as VPN type and click “Advanced”.
- Select “Use pre-shared key for authentication”, then click “OK”.

I’m a writer for uscfr.com. In my opinion, technology should make our lives easier, not more complicated. That’s why I enjoy breaking down complex topics and explaining them in a way that everyone can understand. In my free time, I can be found tinkering with new devices or coding up new apps.