SenderCertificatesPassword property (BizCrypto S/MIME Protect Task)
Contains password to the sender certificates.
Sender Certificates Password
This property specifies password to decrypt sender certificates.
Note that this property is sensitive, and is controlled by the project property ProtectionLevel, as it is described in the article: Setting the Protection Level of Packages. For example, if ProtectionLevel is set to DontSaveSensitive, passwords (and other sensitive data) will be suppressed when the packadge is saved.