Iframe - IE - P3P header

I believe that should be in settings.php. It implies certain things about the site, and the module should not add that, a site administrator (who, hopefully, understands those headers better than I do) should add that to his/her site.

Here's what drupalforfacebook.org has added to it's settings.php.

header('P3P: CP="CAO PSA OUR"');

This is so important! At least it needs to be in the README.txt or something.

Was having an issue with iframe for just IE7&IE8 when it came to authentication and an infinite redirecting and wouldn't load. Didn't happen in Chrome/Firefox/Safari.

Tried everything - disabling modules, caching, etc.

The fix had to do with an issue with IE + blocking iframe cookies because of Platform for Privacy Preferences:
http://www.adamyoung.net/IE-Blocking-iFrame-Cookies

The fix was adding below to the PHP and it worked:

PHP:
header('P3P:CP="IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT"');

I will add a link to http://drupal.org/node/933994 [#933994] in the readme.

I know this has been closed awhile but I figure this could make someones life a little easier if it works for them. I used
header('P3P: CP="We do not have a P3P policy"'); and everything seems to be working fine now. This is not on our production site yet but seemed to fix our IE issue when I tested it.

That's good to know, I added that to the troubleshooting page.

Does anyone know if this solution is out dated? I have a site developed in Drupal 7 and the user sessions are not working in the iFrame when Internet Explorer is used. I have tried the solutions above amonst other variations and I have had no luck. I am desperately seeking a solution. Any help of direction is apprecitated.

Thanks,
Nils

Unfortunately the solutions above are not working in IE 10 and 11.

We have an iframe to log a user in to an app; the iframe uses a class to stay hidden and we then redirect the user to the intended page. In all other browsers the page opens and user is logged in as Iframe has run with no issues but not in Internet Explorer no matter what IE settings I change (lower all crap blocking IE does) it still doesn't work.

I added a p3p.xml (http://OurURL/w3c/p3p.xml) but wasn't sure where the suggested header should be put, so I tried it in the page which is running the iframe, I tried it in the settings.php, in the page.tpl.php but none of them worked:
headers such as:
php header('P3P:CP="IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT"');
or php header('P3P: CP="CAO PSA OUR"');

I'd appreciate it a lot if someone can tell me where the header should be added, or if there is another way of getting Iframe to behave. The XML we are using in the iframe (which again works with eveything except IE) is:

$output = '<div class="hide"><iframe src="https://OURurl/api/xml?action=login&login=';
$output .= $info['email'];
$output .= "&password=";
$output .= $info['pass'];
$output .= '"></iframe></div>';
print $output;

I bumped into this issue and maybe this will help you
http://stackoverflow.com/questions/20428034/setting-p3p-headers-in-apach...

basically, you can set the header on .htaccess file

I also faced same problem where cookies were not being stored in iframe D7(FOR Internet Explorer) for third party sites.Adding this in template.php of my theme fixed the problem-

drupal_add_http_header('P3P', 'CP="CAO PSA OUR"');