we have three colleagues with the same problem, search in outlook doesn't work:
macbook pro intel 13" with big sur 11.2.3 and outlook 16.47
it worked for a long time, but the colleague deleted accidentally emails and used timemachine to restore the emails - since then spotlight doesn't find all emails
new macbook air m1 with big sur and outlook 16.47 this colleague got a new macbook air m1, we did a clean setup without migration assistant, after setting up the mailaccounts we can't find any emails, even if we see the email in the inbox
macbook pro m1 with big sur and outlook 16.47 this colleague normally uses mail.app with no search problems, to have a another example he setup his mail-accounts also in outlook, where the search function can't find anything
they use different types of mailservers - on premise exchange, normal imap-server, office365
so it looks like there is something seriously broken in combination big sur + outlook search
please notice: if we switch on any of these 3 workstations to the new optics, the search works, but because the "new" outlook doesn't support imap-mailaccount, they can't use the new optics.
after switching back to the old optics search doesn't work anymore.
we tried already everything what we could find in discussion forums: - delete spotlight-index from whole disk - delete spotlight-index from outlook-group container-folder - use terminal command to reload the outlook spotlight importer - delete and reinstall office