Background: For whatever reason, each time a user attempts to open an xslx (stand out 2007) file from your intranet using MSIE, the file download dialog translates it as being a "zip" file.

Of course, xslx files really are zip files, but we do not want that behavior. Just open in Stand out, please.


Opera, OTOH, opens the files normally. Is it feasible the fault is my apache configs? or perhaps is mtss is a client-browser-only problem?

This is because IE's strange MIME sniffing at behavior: It essentially attempts to determine towards the file kind of personal files by considering its contents, in some way like Linux's file tool.

You have to then add new MIME-TYPES on the internet-server-side.

Begin to see the comment-thread on this page (from 2009):

Add this to some .htaccess file and throw it in your site: AddType application/vnd.openxmlformats .docx .pptx .xlsx .xltx . xltm .dotx .potx .ppsx

Should fix most of the problems.

Alternatively, you can include this towards the mime.types file situated within the config directory of the Apache web server

application/ .docm
application/vnd.openxmlformats-officedocument.wordprocessingml.document docx
application/vnd.openxmlformats-officedocument.wordprocessingml.template dotx
application/ potm
application/vnd.openxmlformats-officedocument.presentationml.template potx
application/ ppam
application/ ppsm
application/vnd.openxmlformats-officedocument.presentationml.slideshow ppsx
application/ pptm
application/vnd.openxmlformats-officedocument.presentationml.presentation pptx
application/ xlam
application/ xlsb
application/ xlsm
application/vnd.openxmlformats-officedocument.spreadsheetml.sheet xlsx
application/ xltm