The software works fine;
but after paypal payment
when it comes back to my site, to download the product
I get the following error message at the top of the template:

"Notice: Constant YOURBASEPATH already defined in /usr/www/users/florix/templates/florida/index.php on line 20"

and instead the download link the following message:

***************************************************
Error

An error occured while processing your request. This may have various reasons:

* The link to this site is not valid
* you are trying to download a file without paying the fee via paypal.
* You are trying to download a file multiple times. To avoid misuse it is only allowed to download files once.

If you think this is a mistake, please contact us by mail providing us with your paypal transaction id.
****************************************************

What´s wrong?

paypal works
uploaded page in: myweb.com/componets/com_p2dxt/data/text.pdf

index.php
line 17 <?php
line 18 // no direct access
line 19 defined( '_JEXEC' ) or die( 'Restricted index access' );
line 20 define( 'YOURBASEPATH', dirname(__FILE__) );
line 21 ?>