Cloud-Based Public Folders Migration: A Complex Task

Microsoft's Office 365 offers various subscription choices that allow companies to sign up for individual cloud services, such as Exchange Online. However, when it comes to public folders, a feature introduced in Exchange 4.0 in 1996, things get complex.

Public folders give users a shared location to store documents, contacts, and calendars. But when migrating from on-premises Exchange to Office 365, IT administrators face challenges. Microsoft did not offer a way to move modern public folders, also known as public folder mailboxes, to Office 365 until March 2017.

Michael Shaw, a solution architect for Office 365 at Whalley Computer Associates, warned that public folders should migrate last when moving from on-premises Exchange to Office 365. This is because mailboxes in the cloud can access public folders on premises, but not vice versa. He emphasized that public folders should always have access to old, but old cannot access public folders.

Microsoft discourages using public folders for document use due to potential issues when multiple people try to work on the same file. Instead, it steers Office 365 shops to SharePoint Online for document collaboration and the Groups service for shared calendars and mobile device access.