winmail.dat files - now the viewing apps don't work

A few days ago all the attachments from senders who use Outlook/Exchange started coming through as winmail.dat files. My friend suggested using TNEF's Enough, a free app that allows you to view those files. It didn't work, so I also tried a paid tool (Winmail.dat Viewer). It also doesn't work. So now I'm down $2.99 and every time I get one of these, I have to log into webmail and get the file there.

Did Microsoft change something recently to cause this? What steps can I take to fix this issue so that I don't have to get into webmail every time I get a new attachment?