SCRIPT5007: Unable to get property 'value' of undefined or null reference-Record and share programming errors

I have a html form that appears not to be functional in IE10. when click on go button debugging returns:”SCRIPT5007: Unable to get property ‘value’ of undefined or null reference” I have added this tag in my html page

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html contains dropdown menu option for frequency in myform.After selecting any option in dropdown i am calling below javascript function.

function chooseFreqMenu(freqValues,freqTexts)
{
    var cf = document.myform;
    var freq1=document.myform.freq.value; // freq1="d"
    alert(freq1);// displaying freq1 value is "d" (ex:selected 'd' in html dropdown)
// checking some condition for freqValues.
    for(var i=4;i

Originally posted 2013-08-25 00:25:00.