We currently use the mime-type provided by the file upload. On Windows this can be different for the same file type based on the applications installed (i.e. XLS can have one of several mime-types depending if you have office installed, and which version). It's also forgeable.
We currently use the mime-type provided by the file upload. On Windows this can be different for the same file type based on the applications installed (i.e. XLS can have one of several mime-types depending if you have office installed, and which version). It's also forgeable.