Cisco AnyConnect Certificate Validation Failure: How to Fix It

Q: Why does Cisco AnyConnect show certificate validation failure?

This error occurs when AnyConnect cannot verify the VPN server's security certificate. Common causes include expired certificates, certificates from untrusted authorities, or missing root Certificate Authority certificates on your computer.

Q: Is it safe to disable certificate checking in AnyConnect?

No, disabling certificate checking removes an important security layer and should only be used temporarily for testing. Always re-enable certificate validation after testing to maintain VPN security.

Q: How do I get the correct certificate for my organization's VPN?

Contact your IT department or network administrator. They should provide the internal Certificate Authority certificate file (.crt or .cer) that needs to be installed on your computer.

Q: Can I fix certificate validation failure without IT help?

Limited fixes are possible, such as updating AnyConnect, clearing the cache, or checking system time. However, obtaining and installing the correct Certificate Authority certificate typically requires IT department assistance.

Q: Will updating AnyConnect fix certificate validation errors?

Updating may help if the error is due to software bugs or compatibility issues, but it won't fix problems caused by missing or incorrect Certificate Authority certificates, which must be installed separately.

Abstract

The Cisco AnyConnect Certificate Validation Failure error occurs when your VPN client cannot verify the server's security certificate, typically because it's expired, untrusted, or issued by an unrecognized certificate authority. This prevents you from establishing a secure VPN connection to protect your data.