Language detection after Windows 10 Redstone 2 Update


  • Before Windows 10 Redstone 2 Update, our ASP.NET MVC web application detected the browser language set by the user in IE 11 in "Internet Options", using "Accept-Language" header. Here is where we set the language:

    IE lang settings

    After the Redstone 2 update IE 11 does not send the correct language anymore in "Accept-Language" header, and 'navigator' JavaScript object does not contain the correct language either. The current state of the header and the JS object:

    Header's valueNavigator

    No 'German' language anywhere in the values.

    How can the user change the language now in IE 11 to be detected by the application either in the back-end (via an HTTP header) or in the front-end (via 'navigator' object) or somehow else?

    IE version:

    IE version

    • Edited by Vadim Maximov Wednesday, January 10, 2018 10:15 AM IE version added
    Wednesday, January 10, 2018 10:13 AM

All replies

  • Hi Vadim Maximov,

    According to your description, I suggest you should ensure the German (Switzerland) language is added and
    then the language pack is installed (not just available).

    As far as I know, just enable the language will not change the ie language header.

    Best Regards,


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    Thursday, January 11, 2018 9:19 AM
  • Thank you, Brando, but I don't think this is the reason, because in our DEV environments (Windows Server 2012) the same way of changing the language in IE 11 works as expected. And no language packs are installed:

    Windows Server 2012 lang packs

    IE version in Windows Server 2012:

    windows server 2012 IE ver

    So the new "improved" IE has the problem, I guess. Or it is a critical change in the functionality I cannot find any official info about.

    Please, mark as answer, if this helps.

    • Edited by Vadim Maximov Thursday, January 11, 2018 11:51 AM added screenshots
    Thursday, January 11, 2018 11:43 AM
  • So, can anyone please help with this? Is there a way to make IE 11 in a new Windows 10 Redstone 2 Update to switch web site languages (HTTP header "Accept-Language") easily? We use it to test different localizations of the web sites and we cannot test German UI at all now.

    Or, at least, does anyone have the same problem?

    Thursday, January 25, 2018 11:43 AM