VPN L2TP error 789 with Vista / Windows 7

[Myron Schroner]

Hello folks,
I can't consistently connect over VPN using L2TP, I get error 789. Others using that server can connect consistently. Here are some details.

- I'm using Windows 7 but had the same problem with Vista.
- I can connect sometimes, maybe every 10th reboot.
- I've saved copies of system and application event logs and compared them, there are no differences other than the listed order of items that all happened to start in the same second.
- I've saved copies of services running and they're the same.
- I've tried a clean boot using msconfig with all non-ms services stopped and no startup apps running.
- I've tried removing my home router from the equation and using the modem directly.
- Sometimes it works for a clean boot and sometimes not. Same for a full boot.
- We're using pre-shared key authentication.

Any ideas? I've been trying to get this nailed for two days and it's driving me nuts.

In most cases, error 789 is security settings issue. these search results
may help.
a.. VPN error 789
In many cases, VPN error 789 is security settings or 3rd party
software issue ... I'm trying to connect to a l2tp vpn and I receive the
error 789 : The l2tp .

a.. Fixed: VPN error 789
but NOT able to connect by L2TP/IPSec (Error 789)2. at work ... I am
experiencing the same problem (error 789) when trying to connect to

[Myron Schroner]

I've tried it with a clean boot and I've made sure "IPsec Policy Agent" and "IKE and AuthIP IPsec Keying Modules" services were running. As a matter of fact, I did that before posting because of your earlier posts, so thanks for getting me this far. :-)

I still only get success about every 10 reboots. Of course _something_ has to be different about those particular reboots but I can't figure out what it is. I just reboot and try, reboot and try, and sometimes it happens twice in a row, and sometimes it takes ten tries. (Which is a pain when I need to log in to get some work done.)

Any other ideas greatly appreciated... maybe even any ideas about how to tell what's different in the system from one reboot to the next. (Aside from comparing event logs and a list of running services, which I've done.)

Could the order in which services are started matter? (And if so, why would it be wrong sometimes only on my machine but consistently right on other machines?)

I have a fresh install of Windows 7, by the way, from the release code. Just installed last week.

Nope, no Cisco VPN client.

Anyone have any ideas how to troubleshoot this? What might be different on my system the 1 in 10 times that it succeeds? I've looked at system and application event logs and the same events happen after boot. I've compared lists of running services and they're the same.

I'm stumped.

If my memory serves, Cisco VPN can cause this issue also. Do you have Cisco
VPN client in your PC?

Somebody help us this is a serious problem and no one help us