Hi JadeLiang,
I have Outlook for Mac 16.47 (21031401), and am experiencing a very similar problem: all emails seem fine in their mailboxes, and in the webmail.
However, when I search for a specific word (or words), the search returns all received emails with correct dates and all sent emails with "1 Jan 2001".
Trying to answer all the questions you put above:
- Cannot reproduce problem in webmail (search in webmail returns all dates correct);
- yes, issue occurs with all accounts (only the one I use);
- I also have only "Date" do choose in the View > Columns. Date Received and Date Sent are not options any longer. Could this be related to the problem? I thought it was just some strange choice from MSF.
I also looked at what you suggested with the Language Settings for Outlook (I have macOK Big Sur), hence tried changing the language to English, to Portuguese, to Portuguese from Portugal, to English from UK, all to no avail.
Anything else I can try?
Thank you in advance!