The way public folders work has been changed radically in Exchange 2013. Starting from Exchange 2013, public folders are basically stored in a regular mailbox, and then published as public folders. With Exchange 2010 being the last version to support so-called "legacy" public folders, Exchange 2013 is not able to access these folders. As a consequence, if you're in the middle of a migration from Exchange 2007/20102010 to 2013, or are running a mixed environment, and you still have these legacy public folders on your Exchange 2010, you will notice that users with a mailbox migrated on Exchange 2013 will no longer be able to access these public folders. As Exchange 2013 no longer sup  ...