I am trying to upload epub and mobi files

I am using Formidable Pro forms. I have created a form for uploading audio files such as mp3 and m4b it works great.

However when I try to upload epub or mobi files it says these files are not approved and cannot be uploaded. I have searched and read on the Formidable form Pro site which says that it is in the WordPress that must be changed to accept epub and mobi files for upload. Can you help me with this?


  • Michael Bissett
    • Recruit

    Hi @mike, hope you’re doing well today! :slight_smile:

    You can try adding in this code as an mu-plugin, that should enable you to upload those filetypes:

    function addUploadMimes($mimes) {
    $mimes = array_merge($mimes, array(
    'epub|mobi' => 'application/octet-stream'
    return $mimes;
    add_filter('upload_mimes', 'addUploadMimes');

    (hat-tip to eschipul.com for the code inspiration)

    Let me know if this helps please! :slight_smile:

    Kind Regards,


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