KB5026372 Update breaks MS L2TP VPN Client

VPN
1

After installing KB5026372 the MS L2TP VPN Client on Windows 11 crawls to a snails pace and becomes unusable. Any traffic over L2TP is laggy and the L2TP service is practically broken after this update.

Once KB5026372 is uninstalled and the system is rebooted than L2TP starts working normally again.

MS please address this issue as it’s currently not on the known issues list for the update.

It’s causing massive pain for those utilising MS L2TP client on Windows 11.

2

I’m having exactly the same issue.

3

Credit to “Itkon” for posting this solution in the May 9th Announcement post for a quick uninstall of the update.

https://www.reddit.com/r/Windows11/comments/13czkrv/comment/jjpvdxu/?utm_source=share&utm_medium=mweb3x&utm_name=mweb3xcss&utm_term=1&utm_content=share_button

4

Also … broke RDP unless you force-ignore UDP

AT key … [HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\Terminal Services\Client]

set DWORD … fClientDisableUDP"=dword:00000001

Also broke Windows Explorer access to remote drives.

Didn’t find a workaround. Uninstalled KB5026372. Problems resolved.

5

Another work around for this issue is you can install wireshark and open it. It installs npcap and that seems to solve the issue. I went from 1mb down to 90mb+.

6

Ahhh thanks. Less angry users now.

7

Excellent workaround for the RDP issue CBOFF. :+1: