Outlook 2016 - Report Phish button not working

During these weeks we faced Outlook Report Phish but to work properly when submitting suspiciouses emails.

We are sorry we couln't access Report Phish. Make sure have a network connection. If the problem continues please try again later  (Dismiss this message).

Problem was due this Internet Explorer Setting:

  • In Internet Explorer, click Tools button --> click Internet Options. 
  • Click the Security tab, and then select the Internet Sites Zone
  • Select the Enable Protected Mode check box, and then click OK
  • Restart Internet Explorer and outlook

In case icon graphics is not as expected you should proceed, on IE, like below screenshot:

To fix completely problem you need to apply all steps here indicated.