function FormCheck()
{

 if(document.contactform.Name.value == "")
  {
   alert("Please enter your name.");
   document.contactform.Name.focus();
   return false;
  }

 if(document.contactform.Email.value == "")
  {
   alert("Please enter your Email address.");
   document.contactform.Email.focus();
   return false;
  }

 if(document.contactform.Email.value.indexOf('@') == -1)
   {
    alert("Sorry, this is not a valid Email address.");
    document.contactform.Email.focus();
    return false;
   } 

 if(document.contactform.Email.value.indexOf('.') == -1)
   {
    alert("Sorry, this is not a valid email address.");
    document.contactform.Email.focus();
    return false;
   } 

}