[UPDATE]: This post was updated on August 11, 2016.
Since the release of Exchange Server 2007, there have been rumors that Exchange public folders are not going to last long in Exchange. Although they are a huge enhancement as far as data sharing and online collaboration are concerned, since the first release of SharePoint Microsoft tried to convince companies to rather use their separate online collaboration platform for data sharing instead. However, over the past releases of Exchange public folders remained and have been even improved. In Exchange 2013/2016/2019 they are not the same public folders anymore. The newest version of Microsoft’s email server introduced a completely new approach to public folders architecture. Separate public folders databases are now gone and public folders have been moved into mailbox databases. This model results in better reliability (mailboxes can be a part of DAG) but also causes some problems in terms of data migration from legacy versions.
Let’s focus on the main difficulties you may encounter while migrating legacy public folders to Exchange 2013/2016/2019 and find out how to migrate them successfully.