Adding Adobe files to a wordpress site [closed]

Allowing file types outside of WP’s defaults exposes your site to some security risks, and some hosts don’t allow certain filetypes. If your host allows these filetypes, you can use the following function in a plugin or a child theme:

function wpse_file_uploads($mime_types){
    // photoshop
    $mime_types['psd'] = 'image/vnd.adobe.photoshop';
    // illustrator
    $mime_types['ai'] = 'application/postscript';
    // indesign
    $mime_types['indd'] = 'application/x-indesign';
    return $mime_types;
}
add_filter('upload_mimes', 'wpse_file_uploads', 1, 1);

Probably best to put this in a custom plugin because if you or another user switch themes later, you won’t want to lose this functionality.