https://docs.whmcs.com/9-1/tags/duo-security/Recent content in duo-security onHugo -- gohugo.iohttps://docs.whmcs.com/9-1/system/authentication/two-factor-authentication/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/system/authentication/two-factor-authentication/Compares the three 2FA services (Time-Based Tokens, Duo Security, YubiKey), lists where clients and admins configure 2FA, covers server-clock-mismatch error messages, and links troubleshooting articles for common 2FA issues.https://docs.whmcs.com/9-1/system/authentication/duo-security/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/system/authentication/duo-security/Explains retrieving the Duo Client ID, Client Secret, and API hostname from the Duo Security admin portal to configure it at Configuration > System Settings > Two Factor Authentication, the admin email/license-key format Duo uses, and how to reactivate a user’s 2FA after a lost device.https://docs.whmcs.com/9-1/troubleshooting/troubleshoot-authentication/duo-security-login-failures/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/troubleshooting/troubleshoot-authentication/duo-security-login-failures/Covers the Activity Log error “invalid_client: Integration type does not support frameless access” for Duo Security 2FA, caused by Duo retiring its iframe prompt, and the fix: make a login attempt, then activate Universal Prompt in the Duo admin account’s Applications settings.