Body property is just a wrapper around Filename
property. This means that whenever you access Body
property, Pop3 server will internally access file specified
in Filename property, and read or write it for you. This is
very neat feature that can be used for smaller messages.
But, if message is much larger (more than few hundred
kb's) you should consider accessing file on disk
directly.
If Filename property is not specified or is empty
string, Pop3 server will create temporary file for you, and
read and write to it instead of you. You don't have to
delete such file manually, because Pop3 server will
automatically delete it when message object is destroyed
(if for some reason your application generates crash they
will probably not be deleted).