Per this support article and all of my previous experience with Outlook, I should be able to hit the "Esc" key when I have an email open and the window will close.

However, I have Office365 and a major update just went out less than a month ago. Now, when I'm reading an email, I need to use Alt+F4 to close it. Esc doesn't work.

Did a setting change that I'm unaware of? Does anyone know if this is intended behavior?