New Outlook does not show Old emails

Same issue, as of 01/10/2024.

I have a gmail.com account, set up in Outlook for Windows desktop app.

When I archive an email:

• Old version of the desktop app : no issue, it appears in the IMAP/Archive folder and in the search,
• New version of the desktop version : the email instantly disapears after appearing in the Archive folder. The email is not deleted, as I can still find it through gmail or by switching back to the old version.

I haven't found a solution yet to this problem ..

No worries and thanks for your context. The "Outlook" experience varies hugely from client to client, not to mention Outlook.com webmail, and also between Outlook.com hosting and not- Outlook.com hosting.

Are we talking about the same email client, Outlook New on Windows? I don’t see such a setting , or Sync Settings at all, for Outlook.com email, or any of my IMAP accounts—which are the ones where I cannot see old emails in Inbox despite their presence on the mail provider’s server.

My Outlook New client reports “Microsoft Outlook Version 1.2024.814.200 (Production), Client Version 20240809006.12, WebView2 Version 127.0.2651.105”. (Settings -> General -> About Outlook) It’s sad we have to work so hard to make sure we are talking about the same “Outlook”, but Microsoft has created chaos by calling all kinds of vastly different things Outlook.

Where did you set this ?

Email settings gear wheel > select the outlook account. It is the third one down under the heading "sync settings". Change "email sync period" to "all time". It was defaulted to like 1 week.

Where did you set this ?