Paypal checkout is failing

I have a site which I've been working on for around a year now. It's almost at the point of going live - in fact some of the site is already being promoted by our client - but I've just tried to process a transaction for the first time in a couple of months and it's failing. When the Paypal popup loaded I got the following error:

array(22) { ["PCMS_ActivationError"]=> string(115) "There was a problem verifying your serial number. Please contact sales@webassist.com in order to fix this problem." ...followed by further error messages which I've included in the attachment (Error 1).

I've re-input my serial no. into the database but I'm still getting errors - either an internal server error message, or another activation error. Could you take a look for me? Error messages and URL details in the attachment.

Paypal can't be used for zero dollar transactions. You must charge at least $0.01 to use paypal. If you need to support zero dollar transactions you have to bypass any interactions with paypal.

How would I do that? But also, I'm getting activation error or server error messages when I try to checkout any item at any price.

The activation error is because you have the wrong serial number for a powerstore installation. It isn't causing the transaction error.

If you send me the error message when not doing a 100% discount I can try to see what is causing it.

It's not a Powerstore installation though, I built the site using eCart. The error messages were in my original attachment - if I try to checkout without a discount code I get an Internal Server Error:

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, mwilson@linksdesign.co.uk and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 500 Internal Server Error error was encountered while trying to use an ErrorDocument to handle the request.

This looks like a problem on the checkout.php page in the redirect code. Can I see a copy of that page? I can tell you how to fix it.

Checkout.php page is attached, thanks for looking at this for me. I also found another post regarding free items (http://www.webassist.com/forums/posts.php?id=8370) but I'm not sure which form I should put the the IF statement around?

The problem appears to be in having an older version of "framework/library.php".

You can probably make sure you have the latest version of eCart installed and then update and re-upload that file... you may just need to upload that file if you ran the checkout wizard with the latest version of eCart.

Another solution is to bypass the problem and update liens 75-82 from:

<?php

// WA eCart Redirect

if ($VetProCart->redirStr != "")     {

  if (function_exists("rel2abs")) $VetProCart->redirStr = rel2abs($VetProCart->redirStr,dirname(__FILE__));

  header("Location: ".$VetProCart->redirStr);

  die();

}

?>

to:

<?php

// WA eCart Redirect

if ($VetProCart->redirStr != "")     {

  header("Location: ".$VetProCart->redirStr);

  die();

}

?>

I did build it using the latest version of eCart. I've just updated that bit of code but it hasn't made any difference. Also tried re-uploading library.php.

You may have to replace that same chunk of code on the confirm.php page.