Dear WisteriaLane,
Thank you for using Microsoft products and posting in the Microsoft Support Community.
I realise that you can see two different folders in Outlook for incoming and outgoing mail. You can't see a folder (i.e. ‘All Mail’) in which both sent and received messages can be displayed. You want to see all messages in one folder. Please point out if I have misunderstood.
Please allow me to explain to you: in general, mailbox for receiving emails and sending emails will divide the folder into [Inbox] and [Sent Files], so that you can distinguish more clearly between emails received from others and emails sent to recipients by yourself. So it is normal that you don't see ‘All Mail’ folder in Outlook.
If you still want to put all emails (including sent and received emails) into the same folder, you can set up rules to achieve this function.
Log in to Outlook, click [Settings] - [Mail] - [Rules] - [Add New Rule], name the rule ‘Move emails to the “All Emails” folder’, and add the condition ‘Apply to’. to all emails’, add the operation “Move to” a certain folder, this folder you can create a new one, for example, named “All Emails” folder.
Thank you for your patience and support. I really hope that the advice I gave above was helpful to you. Please feel free to reply below and let me know how you are doing.
Best Regards
Vivian.Y - MSFT | Microsoft Community Support Specialist