You can change the trust settings of certificates. For example, if you have verified the fingerprint in a certificate that you received from someone else, you can change the settings so that you explicitly trust all digital signatures and certified documents created with this certificate. You can even choose to trust the certified document’s dynamic content and embedded JavaScript.
A certificate must be explicitly trusted before you can use it to encrypt PDFs for the person associated with that certificate. If you have multiple certificates for a person, set trust levels for at least one of their certificates.
You can also trust a certificate by trusting the root certificate. The root certificate is the originating authority in a chain of certificate authorities that issued the certificate. By trusting the root certificate, you trust all certificates issued by that certificate authority. Exercise caution when trusting root certificates.