Sharing Forms Authentication Cookies across your ASP.NET Web Applications

If you want to share Forms Authentication Cookies across your ASP.NET Web Applications, you will want to take a look at this MSDN article: https://msdn.microsoft.com/en-us/library/eb0zx8fc.aspx

You can then follow this article for generating your MachineKeys: https://technet.microsoft.com/en-us/library/cc755177%28v=ws.10%29.aspx

My previous blog post provides screenshots of how to accomplish this using IIS Manager:
http://samirvaidya.blogspot.com/2015/04/generating-machinekey-for-aspnet.html