2.2.25 [RFC3501] Section 6.4.5, FETCH Command


The specification states that some data items, identified in the formal syntax under the msg-att-dynamic rule, MAY change, either as a result of a STORE command, or due to external events.

Microsoft Exchange Server 2007, Microsoft Exchange Server 2010, Microsoft Exchange Server 2013, Microsoft Exchange Server 2016

Microsoft Exchange Server allows such data items to change either as a result of a STORE command or due to external events.


The specification describes the RFC822.SIZE data item as: "The [RFC2822] size of the message."

Exchange 2007, Exchange 2010, Exchange 2013, Exchange 2016

If the [RFC2822] size of the message is known, then Microsoft Exchange returns that value; otherwise, Microsoft Exchange returns the stored-message size (this is the amount of storage space that the message actually occupies). Microsoft Exchange can be configured to return the [RFC2822] size in all circumstances.