Hi, I have another problem in checkbox,How do i uncheck the checkbox if the value of my td is "E" with a class name "recemp",

I am trying to traverse but i could not get what i want

here is my code
lets say my ajax succesfully request from the server.
Code:
    $.ajax({
	 type: 'post',
	 data: {emp:empno},
	 url: "somefile.php",
	 success: function(dataTable){
	
		$('#loadinDiv').html(dataTable);
		
		$('tr.contents').each(function(){
			if(('td.recemp').attr('value','E')){
			   $(this).next('input[name="cbox[]":checkbox]').attr('checked','checked');
			}
		});      
		
	
	 }
  });

Here is the request came from the server via jquery.ajax

HTML Code:
<table class="maintable">

 <tr  class="class1 class2" >
		<td><span><input type="checkbox" name="cbox[]" value="0002" id="50"/> </span></td>
		<td><span>1</span></td>
		<td class="recemp" value="E"><span>E</span></td>
		<td><span>100</span></td>
		<td><span>Engineer</span></td>
		
</tr>		


 <tr  class="class1 class2" >
		<td><span><input type="checkbox" name="cbox[]" value="0003" id="40"/> </span></td>
		<td><span>2</span></td>
		<td class="recemp" value="C"><span>C</span></td>
		<td><span>100</span></td>
		<td><span>Mechanical</span></td>
</tr>		



 <tr  class="class1 class2" >
		<td><span><input type="checkbox" name="cbox[]" value="0004" id="20"/> </span></td>
		<td><span>2</span></td>
		<td class="recemp" value="E"><span>E</span></td>
		<td><span>100</span></td>
		<td><span>Supervisor</span></td>
</tr>		

 <tr  class="class1 class2" >
		<td><span><input type="checkbox" name="cbox[]" value="0006" id="20"/> </span></td>
		<td><span>2</span></td>
		<td class="recemp" value="C"><span>C</span></td>
		<td><span>100</span></td>
		<td><span>Caschier</span></td>
</tr>	


</table>	
Thank you in advance.