Question

I am trying to write a script which clears the value of all input fields except for one. This script is still clearing the DESCRIPTION input field.

jQuery('.campaign-column').not('active').each(function(index){
    if(jQuery('.campaign-column input[name!="DESCRIPTION"]')){
        jQuery(this+':input').val('');
        }
    });

Answer 1

Simplify:

$('.campaign-column:not(.active) input:not([name="DESCRIPTION"])').val('')

I assume you meant .not('.active') and not .not('active'), since there is no <active> element in HTML. Note, the loop (.each()) in your original code is pointless, since every iteration selects, over and over, the same elements.