Overview
The University of Idaho has implemented an archive policy in Exchange Online which affects how messages are archived in Outlook. This feature is visible in Outlook as the "In-Place Archive", or "Online Archive", to the bottom left of the folder view. Messages are automatically moved to the "In-Place Archive" after two-years.
Note: this is separate from the "Archive" button option at the top of Outlook which is used to move the message to the "Archive" folder in the primary mailbox.
The "In-Place Archive" mailbox is automatically attached to your Outlook view in the left side folder list.
Note: In Outlook Classic, this may be referred to as the "Online Archive".
The folder structure will mirror the primary mailbox folder list *if* the archive folder contains messages which have been automatically migrated.
The default Exchange Online Messaging Records Management (MRM) policy has been set to automatically move messages to the "In-Place Archive" mailbox after two years.
For example, if a message is stored in the folder "Sent Items", and it is over two years old, it will be moved to the "In-Place Archive/Sent Items" folder. An automatic process called the Managed Folder Assistant handles the behind-the-scenes policy implementation and can take 24+ hours to complete management operations.
The "In-Place Archive" is separate from the "Archive" folder and the Archive button. When viewing a message in Outlook, there is an option to "Move the message to your archive folder." This takes the selected message and moves it to the *Primary Mailbox* Archive folder. When the messages in the Archive folder reach the two year policy they will be moved to the "In-Place Archive/Archive" folder.
Example:
1 = Archive Button
2 = Primary Mailbox Archive Folder
3 = In-Place Archive Mailbox Archive Folder
The top search bar in Outlook automatically includes the In-Place Archive mailbox in the search results. No change is required for normal keyword searches. If you are using Outlook search folders, or limiting the search scope to a specific folder, you may need to also include the In-Place Archive version of the folder when messages are over two-years old.
Information from Microsoft on the In-Place Archive is available here: https://support.microsoft.com/en-us/office/manage-email-storage-with-in-place-online-archive-mailboxes-1cae7d17-7813-4fe8-8ca2-9a5494e9a721