Hi Renato,
I'm Cherrelyn, and I’m here to help.
If Outlook search fails with a timeout or “A problem occurred...” message, this may be due to a short search timeout on Exchange or issues with indexing. You can ask your Exchange admin to increase the SearchTimeout value using PowerShell on the server side. On your end, try rebuilding the search index: go to Control Panel > Indexing Options, then Advanced > Rebuild. Also, ensure Outlook is up to date and fully connected to the Exchange server.
I hope this helps, and feel free to reply if you have any other questions.
Warm regards,
Cherrelyn