Full Mailbox Storage Solutions - Outlook

Full Mailbox Storage Solutions - Outlook

Manual Mailbox Cleanup 


1. Deleted Items Folder

Old or unnecessary deleted emails can accumulate quickly.

Outlook Desktop
  1. Go to the "Deleted Items" folder in the left pane.
  2. Right-click on the folder and choose "Empty Folder".

Outlook Web
  1. Click on "Deleted Items" in the left menu.
  2. Select "Empty folder" at the top, or manually check and delete items.
If you want to review items before permanent deletion, open the folder and sort by Date or Size, then manually delete older or larger messages.

2. Sent Items Folder

Sent emails, especially with attachments, take up a lot of space over time.

Cleanup Strategy:
Sort by Size or Date.
Delete emails with large attachments or old messages you no longer need.

Outlook Desktop
  1. Click on the "Sent Items" folder.
  2. Click the "Size" column to sort from largest to smallest.
  3. Review and delete unnecessary items.

Outlook Web
  1. Open "Sent Items".
  2. Use the Filter → Sort by size or date.
  3. Select and delete as needed.

3. Inbox Items Folder - Find and Remove Large Attachments

Attachments are the main culprit of storage bloat.

Outlook Desktop
  1. In the Mail view, use the Search box at the top.
  2. Type hasattachments:yes and sort by Size.
  3. Manually delete emails with unnecessary attachments.

Alternatively, save attachments to your computer or cloud, then delete the email or remove the attachment.

Outlook Web
Use the Search bar: type hasattachments:yes.

Add filters for size (size:>10MB) to find large ones.

Review, save if needed, and delete.

Online Archive

Please contact Ally support to enable this for a user, or a user with Admin access to M365 users if you are not a Managed IT client.

Once enabled, you can set emails to be archived by right-clicking your mailbox > Data File Properties

 

Then in the Pop-up window, go to the Policy tab

If Online Archive is enabled, you will see a drop down box under Online Archive to select the age at which emails will be moved to the Online Archive.

Storage Usage Review

Outlook Web: Settings → Account → Storage.
See what’s taking up space and take action accordingly. From most usage to smallest - GB > MB > KB > B.
1GB = 1024MB
1MB = 1024KB
1KB = 1024B