When you can’t see attachments in Outlook, the problem is usually associated with app settings, antivirus programs, or device limitations. Instructions in this article apply to Outlook 2019, 2016, 2013, 2010 Outlook for Office 365, and. These kind of Outlook issues can affect small and large attachments and a variety of file types. Attachments are one of the most commonly used features in the Microsoft Outlook email app, but it can often be hard finding the attachment function, seeing attachments in Outlook emails that have been sent to you, or knowing when an Outlook attachment has been uploaded to a message correctly.