If you click to download a "file_name.docx" or "file_name.pptx" link, Internet Explorer 7 will try and save the file as "file_name.zip". If you do this, the .zip file after extraction, will not have the correct document in it. To avoid this, follow these steps. Mozilla FireFox is not affected by this and will save "file_name.docx" and "file_name.pptx" just fine.
If you are still having problems, email me at bvalentine@bryankvalentine.com.