Enviar, receber e organizar e-mails no Outlook.com
Note: This is a Portuguese-language forum. However, since you posted in English, I will reply in English.
Hi Eric Mattiazzi,
Sorry to hear you're experiencing this issue.
Based on the information you've provided, you've already tested multiple browsers (Safari, Chrome, and Edge) as well as multiple devices, which makes a local browser or device configuration issue less likely.
Since the problem occurs consistently across different environments, this may be related to a temporary Outlook.com service issue or an account-specific search/indexing problem on the server side.
Unfortunately, this is where the limitations of the community come into play. We do not have access to Microsoft's backend systems and therefore cannot verify the status of your mailbox indexing, search service, or account configuration.
As a precaution, I would suggest waiting a day or two and then testing the search function again. If the issue persists, please contact Microsoft Support, as they have access to internal tools that can investigate potential mailbox or search service issues on the backend.
If you notice any changes or receive any error messages, please feel free to post an update and I'll do my best to help further.