Drag & drop doesn't work in my AA 1.5

I can't open any audio files by dropping them onto the Edit or Multitrack view work area.  These files do open from the menu with FILE/OPEN or the "open" icon.  I'm using Windows 7 on a notebook computer.  On my XP desktop, I have no problem dragging and dropping files onto the AA 1.5 work area to open.

Drag & drop works fine on my AA 3.0 Windows 7 installation.

Solution anyone?  Thanks.