The error message "undefined" can occur when trying to register for a Fortimanager free trial if there is a problem with the registration process.
Here are some possible causes and solutions:
1. Internet connection issues: Make sure your device is connected to the internet and that the connection is stable.
2. Incorrect information: Ensure that you have entered all the required information correctly, including your email address, name, and organization.
3. Server issues: The Fortinet server may be experiencing temporary issues, in which case you should try again later.
4. Blocked ports: Some network configurations may block certain ports required for the registration process. In this case, you may need to modify your upstream device/firewall settings or contact your network administrator for assistance.
If none of these solutions resolve the issue, you can try registering for the Fortimanager free trial using a different device or network.