Exchange Server 2010 introduces an integrated archive solution named personal archives; this solution provides an alternative to personal store (.pst) files, providing you with the means to phase out these files by importing them to the personal archive associated with the user's mailbox. Eliminating .pst files rids you of the many headaches associated with them:
Access from file shares is not supported.
They can be challenging to deal with during a legal or regulatory discovery request. (Searching .pst files scattered across file servers, laptops, desktops, and removable storage can be difficult if not impossible.)
A personal archive is a mailbox that can be used for alternative storage, and is optionally ...