View All Resources

Online Archiving

Other Names: Auto-Expanding Archiving, Unlimited Archiving


Microsoft Exchange Online Archiving (also known as just Online Archiving) is a cloud-based, enterprise-level method of archiving email from Microsoft.  It is an alternative to local archiving methods, such as moving email to .pst files.   Online Archiving enables the user to access their archived email from any location, using the same methods they access their non-archived email.

Online Archiving provides the user with a specialized archive mailbox that appears alongside the users' primary mailbox folders in Outlook or Outlook on the Web (OOTW).  Users can access the archive in the same way that they access their primary mailboxes. By moving email from their primary mailbox to the archive mailbox, users can improve the performance of the primary mailbox by reducing its size.  Email can be moved to the archive mailbox automatically using Archive Policies or manually by dragging and dropping. 

Other benefits of Online Archiving include:

  • Unlimited amount of storage
  • Archive storage quota automatically increased
  • Multi-platform availability

Users can utilize the Office 365 Import service to import .pst files to the auto-expanded archive, up to 100GB.

How to Enable

As of March 6, 2019, Online Archiving is disabled by default for all PennO365 accounts.  To enable it on an account, IT support staff should submit a request to ISC Client Care.

PennO365 Requirements

The Online Archiving feature can be utilized in the following clients:

  • Outlook 2016 or Outlook 2019 for Windows
  • Outlook 2016 or Outlook 2019 for Mac
  • Outlook on the Web


Known Issues

Previous use of .pst files Office 365 Import service can be used to import .pst files to the auto-expanded archive, up to 100GB
Additional Storage might move folders Folders show up in mailbox as a subfolder link under the main folder (see Resources link for example)
Search restriction for additional storage area Email search must be performed in the specific archived folder or subfolder
Mailbox growth restriction Online archiving cannot be used for mailboxes that exceed 1GB of daily growth/another backup solution will be needed
Archive is lost when Online Archiving feature is turned off after being on Move emails from Archive back in to the active mailbox before turning off Online Archive