Word 2007 File Association broken

Hi. I have a Windows Vista machine and MS Office 2007 installed on it. Recently I found that the *.doc files cannot be opened with Word 2007 by double-clicking on it, and those *.doc files are not having the Word icon.

I wonder how to fix the file association? I visited Control Panel\Programs\Default Programs\Associate a file type or protocol with a program, but I couldn't set Word 2007 as default program to open *.doc files (no error message prompted; I selected winword.exe, but Word 2007 still not listed in the program list).

Only *.doc files are affected, *.xls and *.ppt files can be opened by Excel 2007 and PowerPoint 2007 by double-clicking the file icon, and those files have Office icon.

Thanks for reading.

try run the MS Office recovery tool