4. The network device of claim 3 , wherein attaching the at least one file further comprises attaching a plurality of files associated with the selected tag from a plurality of received messages.
3. The network device of claim 1 , wherein the processor enables further actions, the actions comprising: receiving, from the user, a request to attach a file to the message; displaying at least a first level of tags within the PHST to the user; enabling the user to expand or collapse at least the first level of tags to display at least a second level of tags within the PHST to the user; receiving, from the user, a tag selection of a tag from within the PHST; and attaching, to the message, at least one file associated with the selected tag.