The reason behind such corruption can be many like virus infection, system crash, the system is powered down without closing Outlook, or even power failure. Other than this, incorrect installation of Outlook is one reason to encounter this error. Other than the above-mentioned scenarios, it can also occur when you are running Outlook in Compatibility mode, or while using an Outlook profile that was created in an old version of Outlook. xml file with your Outlook name is damaged. However, we can say that it mostly occurs because of Outlook data file corruption or if the.

The set of folders cannot be opened” is uncertain. The exact reason behind the error “ Cannot start Microsoft Outlook.

Even after launching the Outlook application multiple times, you’ll only see the cursor loading for a while, and after that, the error saying Outlook the set of folders cannot be opened will appear. Whenever you encounter the above-mentioned error the Outlook application will fail to open. The attempt to log on to Microsoft Exchange has failed.' How to fix this issue? User Query: I tried to launch Outlook but I got an error message instead: 'Cannot start Microsoft Outlook. This situation can be very frustrating as the error usually pops up out of nowhere stopping you from launching Outlook.

Unfortunately, many users of Outlook 365, 2016, 2013, and 2010 have encountered this Outlook error. The error “The set of folders cannot be opened“ in Outlook has become quite a common issue.

Cant upgrade to outlook 2016 error