Unable to decrypt the authentication cookie generated in C#

[narunachalam]

Generated the cookie successfully using nodejs but decrypting in c# returns null:

FormsAuthenticationTicket ticket = FormsAuthentication.Decrypt(HttpContext.Current.Request.Cookies[".ASPXAUTH"].Value);

[durlabhjain]

I noticed .NET 4.5 compatibility mode has a different encryption/ decryption. I've added relevant code for decryption for now. You can use similar hints to add encryption compatibility for .NET 4.5 compatible auth cookies