Do not write the "Bcc" header into output stream.

Ignore the MIME tree and parse the message as a single-level entity.

Parses and reencodes all headers, even when not needed or modified.

Ignore unparsable headers when parsing mail message.

Always write a content-transfer-encoding, even if ir has a default value of "7bit"

Ignore unparsable S/MIME signature entities when parsing mail message.

Skips checking of text content for text/* entities. When this options is enabled, it is possible to use any characters inside text entities and if quoted-printable transfer-encoding is specified, the encoder persists the original text structure.

Disables encoding of leading 'F', '.' and '-' character in body parts using quoted-printable content transfer encoding. These leading characters used to cause problems to legacy mail trasfer agents, so quoted-printable-encoding them was used as a workaround thata doesn't cause any problems to properly-implemented mail agents.

Only parses message headers and ignores the body.

Do not automatically add a date header if 'date', 'subject' or 'from' headers are missing from a top-level or embedded message.

Do not include encryption key preference attribute in signed message attributes.

Do not include S/MIME options attribute in signed message attributes.

Skip certificate usage check.

Ignore invalid TNEF messages when parsing mail messages.

Skip sender check.

Keep the raw entity body when parsing MIME messages and make it accessible using GetRawContentStream()()().

Keep the input stream open when Load(Stream) method is done.

Try to conserve memory by not preloading attachment content when constructing a message.

Disable a workaround for broken mail clients such as Mac mail that don't correctly parse HTML-only messages. By default, MailMessage class constructs a single-part multipart/alternative structure to solve this. Enabling this flag turns off this behavior.

Load Outlook MSG properties into custom MIME headers. All these MIME headers start with X-Outlook- string.