I got this email from Paypal today, so just passing it along.
Starting the 7th of October, 2013, we will require all incoming requests to have a â€œHostâ€ header which complies with HTTP 1.1 Specifications. This header was not required under HTTP 1.0. IPN and PDT scripts using HTTP 1.0 may start failing with â€œHTTP/1.0 400 Bad Requestâ€ errors after the 7th of October, 2013, which will result in IPN messages not being validated successfully, or PDT scripts not being able to retrieve transaction information.
Action Required before the 7th of October, 2013
Merchants need to update their IPN and/or PDT scripts to use HTTP 1.1, and include the â€œHostâ€ and â€œConnection: closeâ€ HTTP header in the IPN postback script.
Example with Host as www.paypal.com (please make necessary changes if you are using ipnpb.paypal.com):
//Set values for the request back
// post back to PayPal system to validate
$header="POST /cgi-bin/webscr HTTP/1.1\r\n";
$header .="Content-Type: application/x-www-form-urlencoded\r\n";
$header .="Host: www.paypal.com\r\n";
$header .="Connection: close\r\n\r\n";
The PayPal Sandbox has been configured to reject any HTTP requests without the â€œHostâ€ header with HTTP 400 error. Merchants can use the Sandbox environment to certify the changes to their IPN and PDT scripts.
If you check the log section, any PayPal visit should be there.
Somewhere in your PayPal account is an area that lets you know of any return IPN issues - if it can't reach your site for whatever reason, it pauses and comes back several times. Mind you, if that becomes a frequent occurrence, PayPal gets a little testy and lets you know.
Basically update.inc monitors elapsed subscribers, so it won't affect your IPN.
Since I had already tested the changes on SMF, vB and MyBB sites, I didn't run a sandbox test on DF - looks like I'll have to do it after all.
Edit: hmm, just did a test and got this - you have an extra url in your return address - not sure yet whether this arises from you or me, though I don't get it on my site, albeit the DonationsPro version. <div style="text-align:center; margin-top:5px;">
<input type="hidden" name="no_shipping" value="1" />
<input type="hidden" name="cn" value="Comments" />
<input type="hidden" name="image_url" value="http://junglewraiths.net/images/http://www.junglewraiths.net/images/logo.gif" />
<input type="hidden" name="notify_url" value="http://junglewraiths.net/http://www.junglewraiths.net/ipntreas.php" />
<input type="hidden" name="cancel_return" value="http://junglewraiths.net/http://www.junglewraiths.net/index.php?name=Treasury" />
<input type="hidden" name="return" value="http://junglewraiths.net/http://www.junglewraiths.net/index.php?name=Treasury&file=thanks" />
<input type="image" src="modules/Treasury/images/x-click-but04.gif" name="I1" style="border:0; width:62px; height:31px;" />
You are not allowed to view/download this attachment
Server specs (Server OS / Apache / MySQL / PHP / DragonflyCMS):