PHP - Error luego de enviar formulario

success: function(data) {

$(form).ajaxSubmit({

    type:"POST",

    data: $(form).serialize(),

    url:"process.php",

    success: function(data) {

        $('#contact-form :input').attr('disabled', 'disabled');

        $('#contact-form').fadeTo( "slow", 0.15, function() {

            $(this).find(':input').attr('disabled', 'disabled');

            $(this).find('label').css('cursor','default');

            $('#success').fadeIn();

        });

    },

    error: function() {

        $('#contact-form').fadeTo( "slow", 0.15, function() {

            $('#error').fadeIn();