This error "Error: an error occurred while attempting to validate PostalSaver properties. caught an excepted COM error 800404d0. Do you wish to continue processing the mailing?" occurs when running PostalSaver in Mail and previewing the mailing.
This occurs when the CASS certify addresses checkbox is checked on the PostalSaver tab but AddressAccelerator is not installed.
This option requires AddressAccelerator. If you have AddressAccelerator installed, make sure you have the latest version. If you don't have AddressAccelerator, uncheck this box and process the mailing.