Excel 2010: How to open a .TXT file with Excel as the default (or at all) from Windows Explorer

I am unable to open a file with a .TXT file extension in Excel 2010 by double-clicking on the file from Windows Explorer. 

If I attempt to Open With... Excel 2010 is not an option.

If I attempt to set this file extension to open in Excel as the Default Program, it does not work.  I point the Default Programs to C:\Program Files\Microsoft Office\Office14\EXCEL.EXE and nothing happens, Excel is not added to the list of Default Programs.

I can set WORD.EXE and something called Microsoft Office 2010 to open a .TXT file by default, but not Excel.

I can go into Excel and point to a .TXT file and it will open, but prefer the way it has always been.

Any help appreciated.  Thanks, Mark