In my forever battle to beat back my (Outlook) Inbox, I’m in the middle of a tweak that I’m enjoying.
I switched over to show all conversations as “threaded” conversations. This is standard in Gmail and is the default on my iPhone but I’ve never done it in Outlook and had turned it off on my iPhone (it’s on again).
It’s taken some getting used to, but one week in I’m finding getting through my Inbox feels easier and faster, and overall it’s less work to keep track of things.
The way you do this on Outlook is under the “View” menu, click on “Show Conversations.” As a bonus click on “Show Messages from Other Folders” and then you’ll see your own sent replies as well as any filed messages (if you file into folders, which I don’t).
It takes some getting used to, especially because in Outlook there’s no “RE:” in the subject line, so everything feels like a new message. That’s confusing but otherwise I like it.