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RV345 L2TP error 789

We have an RV345 running that I'm not having any success getting L2TP/IPsec VPN setup on. I have setup SSL VPN and can connect with AnyConnect but we would prefer to use the built-in Windows (7 and 10) VPN functionality. It seemed the PDF shared by Robert Raizada would be the ticket even though it is for the 340 and older firmware, but I continue to get error 789: the L2TP connection attempt failed because the security layer encountered a processing error during initial negotiations with the remote computer. The only difference I see between my settings and that PDF is the Start and End IP addresses. What else should I be looking at?
Everyone's tags (4)
Cisco Employee

Re: RV345 L2TP error 789


Regarding the error 789, it seems some settings on the operating system side is not setup properly. Please check the following points…

  • Please make sure the ‘L2TP Passthrough’ and ‘IPSec Passthrough’ options are enabled on the RV345 Router. You can verify the same from the VPN > VPN Passthrough menu.
  • Please disable the Windows firewall and check once as firewall may block the above mentioned two services.
  • Re-enable the IPSec on your computer:

Right click on the start button and select Run option. Type services.msc and click ok. Check for the services "IKE and AuthIP IPSec Keying module" and "IPSec policy agent", if those are not enabled then please enable those services. In case those are already started then you may restart those services once.


Also, you may double click on those two services and select the ‘Startup Type’ as automatic. Restart the VPN service and check the status once.


In case still the issue persists then you may open a service request with us following the below mentioned link for further troubleshooting...


Re: RV345 L2TP error 789

I should note that we connect to a client's VPN using L2TP/IPsec (unknown if their router is a Cisco or not) using the built-in Windows functionality and exactly the same Windows setup as described in the PDF. That is what precipitated the boss's request that we do the same. We can do that fine, just not to our own router via its external IP.

Anyway, I just enabled the 2 passthrough options you noted with no difference. Disabled Windows firewall and restarted both of those services with no difference.

I'm sure it must be something simple that we're missing.

Cisco Employee

Re: RV345 L2TP error 789



Please raise a service request with us following the below mentioned link for further troubleshooting...