ezopenofficeuploadhandler is used for handling uploads of all files with mime type application/octet-stream

In upload.ini.append.php of the ezodf extension:

[CreateSettings]

# Upload handler setting for stock 3.6
MimeUploadHandlerMap[application/octet-stream]=ezopenofficeuploadhandler

A lot of other files are application/octet-stream, and uploading them fails because of this setting.

Workaround: disable ezodf or remove the setting.

Moving the mime types defined in lib\ezutils\classes\ezmimetype.php to an INI file would also allow us to add custom types which now default to application/octet-stream (for example http://en.wikipedia.org/wiki/XPI ).