Help With Polls

[Unholy Prayer]

Ok, there are only two things wrong with the poll system I am currently using is that users can vote more than once. 

1. Users can vote more than once.  All they have to do is refresh the page.
2. Everytime I refresh the page, the POST DATA prompt comes up.

How do I fix these problems?  You can see my poll system at my newly launched website:
http://www.mtechdev.com/ 

[onlyican]

the code snippit checking if they have voted needs to be on that page before the mysql query

[tomfmason]

You could add some kind of session variable. After they vote then you can do something like this

[code=php:0]
<?php
session_start();
//your poll code
//if vote is sucessful
$SESSION['voted'] = "true";
?>[/code]

Now you can place this at the top of your poll form
[code=php:0]
<?php
session_start();
if ($_SESSION['posted'] == "true") {
  echo "You may not vote twice";
   include("something.php");
   exit;
}
?>[/code]