I signed a PDF file by local valid eCert (i.e. HK Post eCert) that supposes a valid one and general public able to counter check via HK Post's LDAP to verify, although signer PC able to receive "Signed and all signatures are valid", recipient side always prompted as "Signer's identity is unknown" and seems they should set signature verification preferences after searched the forum, thus any mean to simplify / automate the process if valid /public eCert used for document signing while I may issue the signed documents for lot of recipients and seems nightmare to told every to repeat the verification preferences in their Acrobat. Thanks.
In the trust identities of Acrobat reader, seems root and intermediate are trusted by default and only action is to trust the user certificate, however, seems the process should repeated at our recipients if various documents issued between different signer, or let me know if it's known issue and need to accept at this stage. Many thanks.