Error
"The L2TP connection attempt failed because the security layer encountered a processing error during initial negotiations with the remote computer."
Resolution
Uninstall the below updates:
Windows 10
(KB5009543)
(KB5008876)
Windows 11
KB5009566
Steps
Use the following steps:
Open Settings
Update and security >Windows updates
Click View update History
If you want to Uninstall updates, click uninstall updates on the top, the page installed updates would open and you can uninstall updates easily by right clicking the specific update.
OR
Just type in Installed updates in the search bar on the taskbar and Install updates would be shown, which can also be used to uninstall updates.
LINKS