Sending, receiving, and organizing email in Outlook.com
Hi
Does the search show no results, keep loading, or display an error? Also, which browser are you using?
Please try opening Microsoft Edge, selecting the three dots (…) > New InPrivate window, then signing in to Outlook.com and searching for an email you can already see in your inbox.
If it still fails, please share what happens or a screenshot with personal details hidden so I can help narrow it down