Thread:Project:Support desk/Cannot upload docx files/reply

MediaWiki 1.15 is vulnerable and no longer supported, and this problem doesn't happen on new versions of MediaWiki. Please upgrade.

As alternative, there's a hack for older versions: Thread:Project:Support desk/Trying to upload a doc file gives error: "Cannot upload this file because Internet Explorer would detect it as "application/msword", which is a disallowed and potentially dangerous file type."