Ok this is very anoying, and it is probably very simple. I want to start my web page with disabled checkboxes, and after particlar line in listbox is selected to enable those boxes. So I put this in onload method

onload = function () {

   for (i = 0; i < document.frmMain.checkgroup.length; i++){

        document.frmMain.checkgroup[i].disabled = true ;

   }

}

it start my page with disabled boxes, now i want do enable them

function enableCheckboxes(){

    if (document.frmMain.Vrste[document.frmMain.Vrste.selectedIndex].value == Sendvici i Rostilj){

        for(i=0;i<document.frmMain.checkgroup.length;i++){

       document.frmMain.checkgroup[i].enabled = true;



        }

    }

}

it goes in to the for loop, but it never enable those checkboxes. I cannot figure it why.

and this is html part, where i call enablecheckbox function:

<select name=Vrste onChange=PopulatePodvrste(); enableCheckboxes();  size=8>

    <option value=Pica>Pica</option>

    <option value=Barbarina domaca trpeza>Barbarina domaca trpeza</option>

    <option value=Slana Palacinka>Slana Palacinka</option>

    <option value=Slatka Palacinka>Slatka Palacinka</option>

    <option value=Sendvici i Rostilj>Rostilj i sendvici</option>

    <option value=Dobro jutro sa Barbarom>Dobro jutro sa Barbarom</option>

    <option value=Chicken Meni>Chicken Meni</option>

    <option value=Posebna Ponuda>Posebna Ponuda</option>

    <option value=Salate>Salate</option>

</select>

And finally actual checkboxes:

<input type=checkbox name=checkgroup >Susam</input><br>

<input type=checkbox name=checkgroup >Cili</input><br>

<input type=checkbox name=checkgroup >Tartar</input><br>

<input type=checkbox name=checkgroup >Urnebes</input><br>

<input type=checkbox name=checkgroup >Krastavac</input>