Tricky issue with the above 4 in one app... IE was blocking a session cookie from my ASP.Net MVC web application when hosted in the Facebook IFRAME. The anti-forgery token in ASP.Net (used to protected against spoof form posts known as CSRF attacks) would fail saying the cookie it was checking against couldn't be found. Turns out the issue was that in medium security settings, IE will "block third-party cookies that do not have a compact privacy policy". And as the app is in the IFRAME it is considered third party with respect to Facebook. To resolve I needed two things: 1) an XML file located at /w3c/p3p.xml containing <META xmlns="http://www.w3.org/2002/01/P3Pv1"> <POLICY-REFERENCES> <EXPIRY max-age="10000000"/> </POLICY-REFERENCES> </META> 2) and a header emitted (in server side code, the meta tag equivalent didn't seem to suffice) Response.AppendHeader("P3P", "CP='IDC DS...
Senior Developer and head of DXP at Umbraco. Previously with Zone, building solutions primarily on .NET and using Umbraco, EPiServer and Sitecore CMS. This blog is used as a repository for various tips, tricks, issues and impressions drawn from the use of technology my work and interests. All words are my own.