435 Certification authority is unknown.
The key database does not contain a certificate for the certification authority.
Obtain the certificate for the certification authority and add it to the key database. When using a SAF key ring, the CA certificate must be TRUSTed. If using RACF key rings and the DIGTCERT and DIGTRING classes are RACLIST'ed, issue the SETROPTS RACLIST (DIGTCERT, DIGTRING) REFRESH command to refresh the profiles to ensure that the latest changes are available.