To resolve the issue of Outlook not properly organizing your emails by size or attachment type, you should follow these steps:

1. Check settings for sorting options.
   Go to the Outlook settings menu and make sure that you have set the appropriate sorting options. It is typically found under the Zoom and View tab or Mail settings tab.
2. Delete outdated emails.
   Removing emails that are no longer relevant will help reduce the amount of emails left in your inbox to make sorting easier.
3. Unsubscribe from promotional emails
   Promotional emails from services and companies can build up quickly and take up unnecessary space in your inbox. Unsubscribing will help reduce the amount of emails in the inbox.
4. Create and use categories
   Using the Categories feature on Outlook is a great way to ensure that emails are sorted correctly and easier to find.
5. Create folders
   Creating folders to help sort different types of emails one step further is a great way to stay organized.
6. Regularly clean out your inbox
   Maintaining a clean inbox reinforces good organization so you can find emails quickly.