Is there a way or special setting (port, proxy, credentials) to receive IPN Response from PayPal for website standard payments?
Actually you'll probably need to contact paypal about this. They shold be able to tell you what port it will be using and what kind of setup it needs on the receiving end that is getting the IPN response. We have a firewall in place but at this point I just don't know enough about IPN Responses to really give you a clear answer.
I'm currently facing the same problem. I initially resolved it by giving my site a High trust level, but this is not ideal. Then I read an article on wrox.com where I obtained the following solution. Add to your web.config (under system.web) <trust level="High" originUrl="http://www\.paypal\.com/.*" />. For the moment this appears to have resolved my issue while maintaining a Medium trust level for the rest of my site. From searching the web it looks like other hosting providers have offered a proxy to allow applications to keep their Medium trust configuration (also because they may not offer anything else). Here are some of my findings: 1.Forum: GoDaddy proxy configuration Proxy URL: http://proxy.shr.secureserver.net:3128 2.Forum: 1and1 proxy configuration Proxy URL: http://ntproxy.1and1.com:3128 Both providers seem to be using port 3128. Just for completion, the code that was failing is: (C#) HttpWebRequest req = (HttpWebRequest)WebRequest.Create(this.PostUrl); where this.PostUrl is either: https://www.sandbox.paypal.com/cgi-bin/webscr OR https://www.paypal.com/cgi-bin/webscr Hope this helps.
