How to change the Microsoft Outlook view back to default/normal view
1. When you are in Microsoft Outlook 2013/2016 click on the view tab.
2. After that click on change view and then click on Apply Current View to Other Mail Folders
3. Next you can choose which folders to apply the view to.
Optionally if nothing is working you can use the Run command outlook.exe /cleanviews to reset the Outlook view settings back to default.