Comment 1 for bug 1302251

The current workaround is to disable fileinfo. You can do this by setting $cfg->pathtomagicdb to boolean false. However, if you've got the mime_content_type PHP library installed, it'll fall back to that as well, and that also identifies docx files as ZIP files. So what you have to do is apply an invalid pathtomagicdb value. This will cause Mahara to attempt to use fileinfo, fail, and fall back to identifying the filetype based on its file extension.

So to do that, you would put something like this in your config.php:

 $cfg->pathtomagicdb = '/dev/null';