Due to the security updates from Microsoft on the Windows 10 platform for SSL traffic. Self-Assigned Certificates are not trusted and can cause connectivity issues from applications using SSL as a form of connecting such as SSLVPN / NetExtender. Typical issues are seen when connecting with NetExtender and getting disconnected right away and a warning error after the disconnect.
Export the SonicWalls Self-Signed HTTPS Management Certificate from Browsers



Once the Certificate if saved the next step is to make it Trusted on the Windows 10 computer.
Adding the SonicWalls Self Signed HTTPS Management Certificate to the Windows 10 computers to make it trusted.










You should not see a warning again for the Certificate not being trusted from this Windows 10 computer or Security Errors and disconnections in NetExtender for these errors. This type of Security Error is typically caused when using a HTTPS URL that does not have a Public Certificate assigned to it.
You can also use a Publicly signed certificate to avoid this process if you prefer:How do I generate a new SSL certificate from my SonicWall firewall?.