function isEmpty(strfield1, strfield2, strfield3, strfield4, strfield5, strfield6) {

strfield1 = document.forms[0].FirstName.value 
strfield2 = document.forms[0].LastName.value
strfield3 = document.forms[0].Address.value
strfield4 = document.forms[0].City.value
strfield5 = document.forms[0].Zip.value
strfield6 = document.forms[0].Phone.value

    if (strfield1 == "" || strfield1 == null || !isNaN(strfield1) || strfield1.charAt(0) == ' ')
    {
    alert("First Name Is A Required Field")
    return false;
    }

    if (strfield2 == "" || strfield2 == null || strfield2.charAt(0) == ' ')
    {
    alert("Last Name Is A Required Field")
    return false;
    }

    if (strfield3 == "" || strfield3 == null || strfield3.charAt(0) == ' ')
    {
    alert("Address Is A Required Field")
    return false;
    }
	
	if (strfield4 == "" || strfield4 == null || strfield4.charAt(0) == ' ')
    {
    alert("City Is A Required Field")
    return false;
    }
	
	if (strfield5 == "" || strfield5 == null || strfield5.charAt(0) == ' ')
    {
    alert("Zip Code Is A Required Field")
    return false;
    }
	
	if (strfield6 == "" || strfield6 == null || strfield6.charAt(0) == ' ')
    {
    alert("Phone Number Is A Required Field")
    return false;
    }
    return true;
}

function isValidEmail(strEmail){
  validRegExp = /^[^@]+@[^@]+.[a-z]{2,}$/i;
  strEmail = document.forms[0].Email.value;

    if (strEmail.search(validRegExp) == -1) 
   {
      alert('Please Enter A Valid Email Address');
      return false;
    } 
    return true; 
}

function check(form){
if (isEmpty(form.FirstName)){
  if (isEmpty(form.LastName)){
    if (isEmpty(form.Address)){
		if (isEmpty(form.City)){
			if (isEmpty(form.Zip)){
				if (isEmpty(form.Phone)){
					if (isValidEmail(form.Email)){
		  return true; 
		  	  }
		  	}
		  }
	  	}
	  }
   }
}
return false;
}

function checkCheckBoxes() {
	if (
	document.MaintenanceInquiry.Interest1.checked == false &&
	document.MaintenanceInquiry.Interest2.checked == false &&
	document.MaintenanceInquiry.Interest3.checked == false &&
	document.MaintenanceInquiry.Interest4.checked == false)
	{
		alert ('You must select at least one product you are looking for regular maintenance on!');
		return false;
	} else { 	
		return true;
	}
}