Using Classic Outlook on Windows for personal email, calendar, and contact management
Hi Mohga,
What changed is the Reading pane got enabled, so a single click selects the message and shows it immediately. That makes it feel like the message is opening when you just want to move it.
In Outlook on the web or the New Outlook app, select the gear icon at the top right, open Mail > Layout > Reading pane, choose Hide reading pane, then save. Go back to your inbox and try moving a message. It should no longer open on a single click.
If you prefer to keep the Reading pane but still select without opening, tell me which Outlook you use exactly and I will give you the checkbox method.