Microsoft Doubles Exchange Online's Public Folder Capacity

Exchange Online now has capacity for "public folder hierarchies of up to 500K public folders," Microsoft announced this week.

That's twice the previous limit of 250,000 public folders. Public folders are typically used to share information within organizations, and apparently some organizations needed more support.

Organizations may be trying to move their Exchange Server folders to Exchange Online, but there's a catch with the new expanded public folders limits. Capacity restrictions are still in place for Exchange Server users. Here's how the announcement explained the matter:

Exchange 2013/2016 customers can still only migrate up to 100K public folders to Exchange Online, and Exchange 2010 customers can only migrate up to 250K public folders to Exchange Online. However, once folders are migrated to Exchange Online, you can expand the hierarchy up to 500K public folders. We are working to resolve these limitations in the future.

Last year, Microsoft documented how to move public folders to Exchange Online from Exchange Server 2016 or from Exchange Server 2013. It's a multistage process and it's not simple. There are also 25GB size limits per folder when moving public folders to Exchange Online, Microsoft had described back then.

Microsoft publishes its Exchange Online limits in this document. According to it, the new 500,000 limit for public folders in Exchange Online is available across Office 365 Business Essentials, Office 365 Business Premium, and Office 365 Enterprise E1, E3 and E5 subscription plans. It's not available with the Office 365 Enterprise F1 plan.

About the Author

Kurt Mackie is senior news producer for 1105 Media's Converge360 group.


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