Hi Salvatore,
the case on Outlook is different, cause it will show you the alternative information in all the links, even if they dont have alt or title.
To see that your "alt" or "title" works, open the email in a browser (by clicking on the message "If there are problems with the way this message is displayed, click here to see it in a web browser").
Opening the email in the browser helps you to understand if the problem is coming from your html in AC or from the email provider.
Thanks,
Badr.