SSL VPN connection to ZyWALL USG 300 does not work from Windows 11.

Piliya

After installing SecuExtender_Windows 4.0.4.0 on Windows 11, SSL VPN connection to ZyWALL USG 300 works! But after restarting Windows 11, the SSL VPN connection stops working.

Why is the SSL VPN connection not working on Windows 11? Why does it stop working after rebooting Windows 11

From computers running Windows 10, the SSL VPN connection to the ZyWALL USG 300 works.

We tested the connection on two new laptops with Windows 11

We use the latest version of SecuExtender_Windows 4.0.4.0

ZyWALL SecuExtender.txt

ZyWALL USG 300 version. 3.30(AQE.7)ITS-WK48-r74988, supporting TLS1.1., TLS1.2

Attachment logs

lalaland

Windows 11 is not in SSL vpn client support list, but my windows 11 21H2 works fine without issue after reboot.

Zyxel_Cooldia

Hi @Piliya ,

Welcome to Zyxel community.😀

You can check if the virtual NIC MTU is 1370 in Device Manager.

It would have connection issue if it is 1500.

Piliya

No, if the MTU is 1500, the connection doesn't work too

Zyxel_Cooldia

Hi @Piliya ,

Please provice the result of windows CLI netsh interface ipv4 show subintrfaces.

We would like to check SecuExtender Virtual NIC MTU value.

it should be 1370.

Piliya

Yes, checked, MTU is 1370, but  connection doesn't work 

Zyxel_Cooldia

Hi @Piliya ,

Please help to check if SecuExtender Helper is running after reboot.

windows control panel > administrative tools > services

Piliya

Yes,Helper is running after reboot, If it did not start, there would be no logs