VPN stop working on Windows 10 Pro

[Tony-CTI]

I have had two calls this morning with user that connect using Windows VPN to the MX, saying the connection is broken.

One person was connected at 7:00am, then after a restart, could not connect. (they think there was an update)

"L2TP connection attempt failed ..." I verified all the settings and the connection to the MX works fine.

I recall this happened a couple years ago with a February update and MS released a fix. 

I was wondered if anyone else is seeing this yet.

I do not see any other postings on this today!

Thanks for you thoughts,

Tony

[alemabrahao]

Have you updated Windows recently? The problem is probably related to an operating system update. Which doesn't surprise me. In other words, there is nothing related to Meraki.

[Tony-CTI]

Thanks- I am now uninstalling this mornings update. We will see.

[Tony-CTI]

I have uninstalled:

2024-06 Cumulative Update Preview KB5039299
Security Update KB5039211

This update fails to uninstall: Update MS Windows - KB5037849

Of course MS is trying to reinstall so stopped Service:

Connection to VPN still not working.

[rhbirkelund]

Instead of uninstalling the windows update, try reconfiguring ClientVPN entirely on the Windows machine.

[Tony-CTI]

Thank you for the recommendation. I can try that, but I have 50 or so possible VPN users on Windows 10 where this could be the next problem.

Not sure I have that many hours. 

I see this in an old post, but it also wants to delete the VPN and rebuild. 

Add to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\PolicyAgent
RegValue: AssumeUDPEncapsulationContextOnSendRule
Type: DWORD
Data Value: 2

[alemabrahao]

Try the Smart VPN, you can configure a L2TP connection on it.

https://www.draytek.com/products/smart-vpn-client/

[Tony-CTI]

Thanks - Looks good, but we have some DoD clients and they are "limited" to what can be used.

[rhbirkelund]

I think I remember @PhilipDAth made a script once that’s publicly available that configures L2TP vpn. Philip, do I remember correctly?

[alemabrahao]

Here is It.

https://www.ifm.net.nz/cookbooks/meraki-client-vpn.html

[Tony-CTI]

I will check this out! 

[Tony-CTI · Accepted solution]

I found the solution (outside this forum)! After deleting and rebuilding the VPN, I went into Device manager > Network Adapters and removed L2PT, PPTP and SSTP. Then rescanned. Not sure which one was causing the issue, but I could connect instantly. 

Thanks for all the suggestions.