RRAS Problem

Posted on 2006-03-19
Medium Priority
Last Modified: 2008-01-09
When I am using a VPN (L2TP/IPSEC) to connect to our RRAS server. I am getting an error messages "Error 789: The L2TP connection attempt failed because the security layer and when I try again I get an error message Error 792: The L2TP connection attempt failed because security negotiation timed out. Any ideas why I am getting this error message.
Could any one tell what ports need to be opened for L2TP/IPSEC and what are protocols on which the L2TP/IPSEC.
Question by:life_j
  • 2
  • 2

Expert Comment

ID: 16232684
L2TP/IPSec traffic uses UDP ports 500 and 4500 to create and maintain the connection and IP protocol 50 to send data. Allow these ports to and from the firewall.

Here are a couple of reasons for the error messages you are receiving.

Error 789

Error 792

If these don't work, try the following to do some basic troubleshooting and information gathering and report back.

Expert Comment

ID: 16234139
"Error 789" error message when you use an L2TP VPN client through a Windows 2000 Terminal Services client session

How to configure a L2TP/IPSec connection using pre-shared key authentication

Mutual authentication methods supported for L2TP/IPSec

Test the connection first using L2TP and a pre-shared key. Once it is working properly with a pre-shared key all of the other pieces of the puzzle fall together seemlessly.

You can use IPSEC over L2TP -


Otherwise, troubleshooting steps are here:


The timeouts suggest that port 500 is being blocked along the way.


Check your Ethernet Card :-

Author Comment

ID: 16244198
No  I am getting an error: 781 No valid certificate available.
Evaning after installing the certificates on both the server and the client

Accepted Solution

partex earned 1000 total points
ID: 16248706
Here are a few more things to look at.

Sorry to leave you on this but I am headed out of time for a week and will not be around a computer.  Sunilcomputer, could you pitch in and see them through on this?

-->I am assuming the certificates you are installing are created to support IPSec communications...
If there is something corrupted with the certificate, you could try using pre-shared keys to test out the connection. If that works, then you know for sure you are dealing with a problem certificate.

Error Connecting to <Connectoid Name>
Connecting to <IP address>...
Error 781: Encryption failed because no valid certificate was found.

This issue can occur because of one of the following reasons:

• The certificate on the virtual private networking (VPN) server is not a valid machine certificate or is missing. If the VPN server got a certificate during the Certificate Authority installation, this certificate is not valid for IPSec machine authentication.

• The IPSec Policy Agent service is stopped and started without stopping and starting the Routing and Remote Access service on the remote computer.

• The IPSec Policy Agent service is not running when you start the Routing and Remote Access service.

To resolve this issue, do one of the following:
• Install a valid machine certificate on the VPN server.
• Stop and start the IPSec Policy Agent service, and then stop and start the Routing and Remote Access service on the remote computer. To do so, use one of the following methods.

Method 1
1. Click Start, point to Programs, point to Administrative Tools, and then click Computer Management.
2. Double-click Services and Applications, double-click Services, double-click IPSEC Policy Agent, click Stop, click Start, and then click OK.
3. Double-click Routing and Remote Access, click Stop, click Start, and then click OK.

Method 2
At a command prompt, type the following commands pressing ENTER after each command:
net stop policyagent
net start policyagent
net stop remoteaccess
net start remoteaccess

NOTE: The IPSec Policy Agent service must be started when the Routing and Remote Access service initializes.

Author Comment

ID: 16253368
When I try connecting with a pre shared key, I am getting an error message 792 and when I am tring to connect with the certificates I am getting an error message saying 781.

Let me explain you completely what I tried.
We have a SBS on which we installed RRAS to accept incoming conenctions for PPTP.I installed certificate services on the SBS .I manually installed the certicate on the server and then from my home pC I connected to my SBS server through PPTP and downloaded the certificate  by typing in the browser http:\\SBS\certsrv.
I changed the PPTP connection to use L2TP/IPsec but wasn't succesfull.
Then in connection properties changed as follows ->secuity-> I changed to Advanced (custom settings)-> use EAP. But this attempt has failed too.
Any thoughts.

Partex I did what you said in the above comment. With no luck

Featured Post

Prep for the ITIL® Foundation Certification Exam

December’s Course of the Month is now available! Enroll to learn ITIL® Foundation best practices for delivering IT services effectively and efficiently.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I use more than 1 computer in my office for various reasons. Multiple keyboards and mice take up more than just extra space, they make working a little more complicated. Using one mouse and keyboard for all of my computers makes life easier. This co…
The article covers five tools all IT professionals should know about, as they up productivity by a great deal!
This is used to tweak the memory usage for your computer, it is used for servers more so than workstations but just be careful editing registry settings as it may cause irreversible results. I hold no responsibility for anything you do to the regist…
Hi friends,  in this video  I'll show you how new windows 10 user can learn the using of windows 10. Thank you.
Suggested Courses

807 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question