For those of you running Windows 10 Insider Preview build 10532 and you’ve updated the Mail app with the recently released update from the Windows Store, you will notice a new setting that allows you to disable conversation view. Conversation view is Microsoft’s method of displaying emails by threads rather than by date.
In previous versions of the Mail app, Microsoft made conversation view a requirement rather than an option. With this new update, those who prefer the old fashioned method of viewing emails can now enjoy the app (first spotted by Mary Jo Foley at ZDNet).
All you have to do open Settings, tap or click Options, and adjust the “Show messages arranged by conversation” setting. This feature is currently only available for those who are running Windows 10 build 10532 and the most recent Mail app update.