Trim your mailbox in 9 quick steps

Start by checking the size of your mailbox.
1. On the Go menu, click Folder List.

2. Toward the bottom of the Folder List, click Folder Size. The Folder Size window displays and you can now see the size of your mailbox and each folder in it.

3. Note which folders are largest in size (perhaps your Sent Items folder or Inbox). Then click Close.

4. Select one of the large folders you noted.

5. On the View menu, click Arrange By and then Size. Make sure Show in Groups is selected on the same submenu.

6. Your messages will be sorted into groups according to size — such as "tiny" and "enormous."

7. Go through the largest group first and delete everything you can to make the greatest overall impact on your mailbox size quickly.

8. Repeat step 6 for all of your large folders.

9. Finally, select your Deleted Items folder, and then click Tools and then Empty "Deleted Items" Folder. Click Yes.