Word file problem

I just upgraded microsoft word from 2003 to 2007. When I uploaded a new file created in word 2007 into AirSet, it apparently doesn't recognize it as a word file - it put a question mark icon before the name, and when I try to open it, it makes me go through a box asking if I want to download the document. When I click OK, it takes me to another box asking "What should Firefox do with this file? Open with (drop-down menu of choices, including Word), or Save File. I just want to double click the file and open it in AirSet like I did before with the old Word 2003 files.