function checkEntry() {  
 // ref to form
 var theForm = document.getElementById('contactForm');
 var errMsg = document.getElementById('form_error_msg');
 var labelColor =document.getElementsByTagName('label');
 var theResult = true;
 var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
  
   // check for values in all fields:
 var reqFields = new Array();
 reqFields[0] = theForm.email;
 reqFields[1] = theForm.email_conf;
 reqFields[2] = theForm.opt_in;
 for (var i=0; i < reqFields.length; i++) {
  if (reqFields[i].value == '' ) {     
  //reqFields[i].style.border = "2px solid red";   
   labelColor[i].style.color = "#ff0000";   
   theResult = false;  
  } else {
    labelColor[i].style.color = "#fff";  
  }
}
 if(reg.test(theForm.email.value) == false){
 //theForm.email.style.border = "2px solid red"; 
   labelColor[0].style.color = "#ff0000";         
    theResult = false; 
 }else {
    labelColor[0].style.color = "#fff";  
  }
    
 if(theForm.email_conf.value != theForm.email.value){
 //theForm.email_conf.style.border = "2px solid red"; 
   labelColor[1].style.color = "#ff0000";      
    theResult = false; 
 }else {
   labelColor[1].style.color = "#fff";  
  }
  if (theForm.opt_in.checked == false){   
  labelColor[2].style.color = "#ff0000";    
    theResult = false; 
 }else {
   labelColor[2].style.color = "#fff";  
  }
  
 // display errors if necessary
 if (theResult == false) {
   errMsg.style.display = "block";
  errMsg.innerHTML = "Sorry, we've found some errors (highlighted below)... Kindly ensure you've entered your details correctly";
 } else {
  errMsg.style.display = "none";
 }
 return theResult;
}