Internet Mail Client Control FAQs/Objects/Section Object
Why doesnít the Section Object encode the Filename property using RFC 2047?
ID: S18E30 DATE:
The filename property corresponds to the
Section 5 of RFC 2047 defines three situations under which encoded-words are allowed in MIME headers and none of these apply to parameters for these fields.
Since using encoded words in these places would result in a non-compliant message the library does not encode the filename.
If you really wish to encode the filename you can manipulate the section's header directly: