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multipart mixed

Headers & MIME

Content-Type and MIME Structure in Email: Multipart, Encodings and Boundaries (RFC 2045-2049)

Alaa 28 August 2026

Content-Type and MIME structure in email: the RFC 2045-2049 rules for multipart/alternative, multipart/mixed, multipart/related, and their nesting. Covers boundaries, character sets, the four ...