Security Alert on Outlook with Office 365 email

Question

Hi, 
 Our company using Office 365 email. 
 Sometimes we are getting an security alert from MS Outlook saying that "The security certificate was issued by a company you have not chosen to trust..." as attached below: 
 
 Please advise how to solve this issue on Sophos Firewall. Thank you!

lferrara · Answer

David, 
 which Firmware version are you running? 
 Since 16.05 MR4 the issue has been fixed by disabling micro-app scanning. more info on this thread: 
 https://community.sophos.com/products/xg-firewall/f/web-protection/75282/sophos-xg-breaks-ssl-when-connecting-to-outlook-anywhere/292551#pi2151=4 
 Regards

lferrara · Answer

David, 
 I moved the thread to the right forum. 
 I guess you are using decrypt and scan. You need to create an https exception. Have a look at this thread: 
 https://community.sophos.com/products/unified-threat-management/f/web-protection-web-filtering-application-visibility-control/73929/webfilter-and-https-outlook-office-com-or-https-outlook-office365-com-host-not-found-help 
 Regards