Applies To 

Accounts with email access.

Starting in May 2025, Exchange Online Archive mailbox will be gradually enabled in all accounts with email access.  No user action is required.

 

What is Exchange Online Archive and why should I use it?

An Exchange Online Archive mailbox stores Outlook items without using up storage quotas.  Once enabled, you will see an empty Exchange Online Archive folder in the Outlook Folder Pane.  You can move emails and other items to the Exchange Online Archive folder.

You can move items to the Exchange Online Archive mailbox either manually or automatically.

 

 

Solution - How to move emails to Exchange Online Archive
Note for Alumni @Link Email accounts: Automatic archive with a retention period of 2 years is enforced.

• Manual archive
       For those who need precise control and their Outlook items mainly stored in a single or a few folders.
  
  
  • Emails: Drag-n-drop them into Exchange Online Archive folder.
       
    
    
  • Calendar, notes, and tasks:  Click More Apps > Folders to show the corresponding folders in the Exchange Online Archive, then drag-n-drop items into the appropriate folder.
    
       
        
    
    
    
• Automatic archive
      For users who are too busy to archive items themselves, or who have Outlook items spread across a large number of folders/subfolders.
  
  
  • Outlook will regularly check and automatically move items older than a specified time (1, 2, 3, 4 or 5 years) to the Exchange Online Archive folder.  You don't need to have Outlook desktop app opened.
  • Depends on your set up, items including emails, calendar items, notes, and tasks will be archived.
  • Archived items will retain their original folder structure.
    
       
    
    
  • How to set up?

 

 

Setting up automatic Exchange Online Archive

1. Launch Outlook desktop app (in Classic mode).
   
   
2. In the Folder pane, select Inbox (or a folder to which you want to apply an online archiving policy).
   
   

   ⚠️Important! Automatic Exchange Online Archive policy will be applied to the selected folder and its subfolder.  That means: If you select Inbox, the policy will only be applied to Inbox and its subfolders.  Folders outside (e.g. Sent Items) will not be affected. If you select your email address (i.e. alias@cuhk.edu.hk) in this step, the auto archive policy will be applied to all folders, including Calendar, Notes, Tasks, etc., as the latter are technically a subfolder of your email address. For most users, applying the Automatic Online Archiving policy to the Inbox and Sent Items folders should be sufficient to effectively reduce mailbox storage. For first-time users, consider applying the policy to a folder with the least impact, such as Sent Items, to familiarize yourself with this feature.

   
   
   
3. On the ribbon, click Folder > Policy.
      
   
   
4. In the Properties dialog box, under Online Archive section, select the number of years that items older than will be archived. Then, click OK when done.
   
       Tip:  See the next section if no policies were shown.
   
      
   
   
5. You will receive a message inform you the changes are applied and click OK.
      
   
   
6. Repeat the process if needed. Sub-folders will follow their parent folder’s policy. For better manageability, we recommend that you keep the assignment simple.
   
   
7. It may take up to 7 days for the policy to take effect.
   
   
8. (Optional) If you are using Outlook on the Web, click menu (…) button next to the folder > Assign policy to select the archive policy you’d like to apply.
   
      
   
   

 

Adding Archive Policy

Follow these steps if you don't see any archive policy.

1. Visit the Retention policies setting in Outlook on the web.
   
   • If you are using Outlook desktop, on the ribbon, click Folder > Policy.  Then click Add or Remove Retention Policies link.
     
        
   • If you are already in Outlook on the web, click Settings > Mail > Retention Policies.
     
     
2. In the Retention policies screen, click + Add new policy link.
   
      
   
   
3. Check all policies, the click Save button.
   
       Note:  If you don't see any policy here, it means Exchange Online Archive and its policies have not been enabled in your account.
   
      
   
   
4. The policies should be added.  If you are using Outlook desktop app, please wait for a while and restart Outlook for the changes to take effect.

 

If you have been following the guide to set up automatic archive, click here to go back.

 

 

#Exchange Online Archive #In-Place Archive #Manual Archive #Automatic Archive