Sometimes, the obstacle isn't the VPN at all, but aggressive third-party security software or local firewalls. These tools can intercept or block the SSL/TLS traffic used for certificate verification. While we don't recommend disabling security software, you can whitelist the GlobalProtect process names to ensure its traffic flows freely.
"I think I know what might be causing the issue," Ryan said. "If your laptop's clock is not in sync with our servers, the certificate verification will fail." globalprotect vpn failed to verify certificate
If you have tried everything above, consider these final steps. Sometimes, the obstacle isn't the VPN at all,
"Try to download and install the new certificate, and then reconnect to the VPN," Ryan instructed. and then reconnect to the VPN