Office 2013 has this nasty habit of opening Word, Excel, and other Office email attachments in “Reading View,” which is a stripped-down read-only mode that exists in Office 2013. Turning it off is simple enough: simply click File > Options and uncheck the setting labeled “Open email attachments and other uneditable files in reading view.” It’s that simple.
But what if you’ve got a network full of users that need to have this feature disabled? Well, there’s a registry setting for that. Using login scripts, group policy, or some other method, set the following registry key to 0: