Merge certificate into your User ID

If you are merging a flat certificate into your User ID, you are prompted with the "Merge Certificate Into Your ID File" dialog box. This dialog box tells you about the new certificate information that you can import into your User ID. Assuming that you want to accept the new information into your User ID, there is also a check box allowing you to trust other certificates signed by this flat certifier. This check box provides you with a convenient method to set up trust for flat certificates of others. If you trust the certifier, you will trust all certificates issued by the certifier. For example, if you trust the certifier you can access all of the servers that have that flat certificate or have a flat certificate issued by the flat certifier. If you don't trust the certifier, you cannot get access to these servers.

If you don't mark the trust check box now, and you want to trust the certificate later, you can accomplish the same thing by setting trust for the flat certifier in the Identity of Others > Authorities section of User Security. See Certificate authorities and the certificates they issue.