When connecting to a VPN, no one wants to get a “connection failed” message. However, that can happen from time to time on Windows 10 with Error 789. The actual error message you receive is “The L2TP connection attempt failed because the security layer encountered a processing error during initial negotiations with the remote computer”. Fortunately, this issue can be easy to fix and it may be on your machine. This error usually occurs because there is an improper setup when you try to connect to an L2TP server. That can cause failures before you actually connect. That said, it could also be an indication there is an incorrect configuration in your Win10 install, but there are other factors as well.
How to Fix Error 789 for Windows 10
To resolve this error, there are some steps you need to take.
- Check the certificate – This is the easiest thing to do. All you have to do is make sure the correct certificate is used on both the server and the client side.
- Re-enable IPSec on your computer – This one is a bit more involved, but we will simplify it for you. Right click on the Windows icon in the lower left hand corner and select Run. When the prompt comes up, type in services.msc. From this point, look for IKE and AuthIP IPSec Keying Modules and under that heading, find the IPSec Policy Agent. Now, check the status. If it says started, click on it to restart. If the started option is disabled, enable it. Next, change the Startup Type from Manual to Automatic. Save your changes, and restart your VPN service.
- Reset the network adapter – Right click on the Windows icon in the lower left hand corner and select Device Manager. Find the Network adapter and right click on it to Uninstall. Now, restart your computer and that should certainly fix the issue.
And there you have the solutions to solving the Error 789 connection error when using L2TP. Of course, if these steps do not solve your issue, we suggest contacting the support of the VPN company you are using for further assistance.