Why are session values 'null', when I use an underscore "_" in my domain name?

Question

I am using ASP.NET MVC4, .NET Framework 4.5 and IIS8. My application can be invoked via the url http://vm_windows8. On first request, the following code snipped will be executed:

Session["Value"] = "MyStoredValue";

On a later request the value will be extracted from the session:

if(Session["Value"] == null)
    throw new Exception("Session 'Value' is null.");

// ... code ...

Every time, the Session["Value"] is null. But when I remove the underscore from the url http://vmwindows8 the session is not null all works as expected.

Does anyone know the issue / solution using underscores "_" in the url in combination with sessions?

Are you sure that session has been started before your code? — user3244721, Jul 03 '14 at 10:25
Are you using IE? I think it fails to write cookies when there's a underscore. — RobH, Jul 03 '14 at 10:26
See http://stackoverflow.com/questions/794243/internet-explorer-ignores-cookies-on-some-domains-cannot-read-or-set-cookies — khellang, Jul 03 '14 at 10:29
@khellang: thank you, you are right. Should I delete this question because of possible duplicate? — Simon, Jul 03 '14 at 20:14

score 2 · Accepted Answer · answered May 01 '15 at 00:58

2

Sessions and cookies are blocked by the browser if you make use of special characters

https://support.microsoft.com/en-us/kb/316112

answered May 01 '15 at 00:58

Bajju

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Why are session values 'null', when I use an underscore "_" in my domain name?

1 Answers1