A large message can be stored by separating the message into an envelope portion containing information such as headers, protocols, and addresses, and a payload portion containing items such as file attachments. The envelope portion can be stored in local storage, while the payload can be stored to a persistent store. The message can be processed incrementally, such that the entire message is never in system memory. Once the envelope portion is processed, the payload portion can be read in increments without being processed, and those increments written directly to the persistent store. Alternatively, the payload can be streamed to the persistent store. A pointer in the envelope can then be used to locate and retrieve attachments from persistent storage.This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.