Microsoft Word/Excel Document Downloads

I am running a site similar to a company intranet portal. Users need to be able to download and upload Word and Excel files. The problem I am having is that users are able to download but once a Microsoft word or excel file is downloaded it is in a read only format. However, when I download the document logged in as the administrator it downloads as an editable document.

I changed the permissions on my FTP client to allow users to read and write. Maybe I did something wrong?