I have a page with a checkbox that is disabled/reenabled with javascript on button click. If I never disable the checkbox then its value is correctly POSTed, however if I disable the checkbox even once it gets posted without value (posts as "name=" even when checked). I have inspected the POST value through firebug. Why does it behaves like this? Am I missing something? I ve read somewhere that disabled controls are not posted, thats OK, but this control is not disabled when the submit is clicked. I am using ASP.NET with more complex setup to test this, but essentially this is the core of the problem. The brower is FF latest. I found very similar question, however without an answer: disabled control being reenabled but still not posting back contents to server