Certificate issue occurs in outlook
Security Certificate Warning in Microsoft Outlook When you try to connect to an Exchange server in Outlook 2016, you receive one or more of the following error messages: Information you exchange with this site cannot be viewed or changed by others. However, there is a problem with the site's security certificate. Check your Outlook is up to date. Outlook is up to date and still, you were facing the issue. Important Follow the steps in this section carefully. Serious problems might occur if you modify the registry incorrectly. Before you modify it back up the registry for restoration in case of problems occur. Exit all Microsoft Office applications. Start Registry Editor: In Windows 10, go to Start, enter Regedit in the Search box, and then select regedit.exe in the search results. In Windows 8 or Windows 8.1, move your mouse to the upper-right corner, select Search, enter Regedit in the search text box, and then select regedit.exe in the search results. In Windows 7 or Windows