What additional requirement must be fulfilled when using wildcard certificates in your organization before federating?

When using wildcard certificates in your organization before federating, it is essential to import the root certificate into your portal. This step is crucial because the root certificate establishes a chain of trust between the server and the clients connecting to it. By importing the root certificate, the portal can recognize and validate the wildcard certificate, ensuring that all communications are secure and trusted.

Having the root certificate installed enables the portal and its users to trust any subdomain secured by the wildcard certificate. This is particularly important in environments where multiple services or applications may be operating under subdomains of the main domain name. It ensures that users can connect to these subdomains without encountering security warnings, as their connections will be verified against the trusted root.

Other options presented do not address the fundamental requirement for ensuring trusted secure connections in the context of wildcard certificates. Updating client certificates, converting wildcard certificates to standard format, or using a secondary certificate for redundancy may be relevant in different contexts but are not necessary specific prerequisites for federating with wildcard certificates.