Pixel tracking problem in PHP

Question

Let me first explain what i am trying to do:

step 1 : domain-a.com -> cookie is set using a redirecting PHP script(placed on domain-b.com) when a link to domain-b.com is clicked from this domain
step 2 : domain-b.com->main website -after a certain browsing user reaches domain-c.com
step 3 : domain-c.com -> when user reaches the thankyou page I placed an img tag with src = PHP confirmation script. (which confirms the cookie-placed on domain-b.com)

Everything is working like charm with Chrome and FF, but IE is not able detect or recognize the cookie inside the confirmation script on step-3.

I am not able to find any specific reason for this.

I will really appreciate if anyone can help on this.

Answer 1

Try adding all three domains to your "trusted sites" in IE. If this fixes it, you know it's a cross-site/cross-domain policy issue, which IE can be really picky about. This may not present an immediate solution, but at least you'll know the cause.

Answer 2

By default IE won't allow "3rd party cookies". Tools > Internet Options > Privacy Tab