In Outlook 2019 on Windows 10, I'm having a strange problem trying to enter appointments into Outlook. In short, Outlook keeps trying to set the start and ends time for the appointment for "a.m.", even if I select a p.m. time, either from the drop down menu or by typing in the time (like "3 p.m."). The problem goes away if I set Windows to use 24 hour time, but I don't want to do that.

I had this same problem in Outlook 2010.