Windows Server IIS loves to tell the world that a website runs on IIS. It does so with the Server: header in the HTTP response, as shown below. In this post I'll show you how to remove HTTP response headers in Windows Server IIS. You don't want to give hackers too much information about your servers, right?.

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In this post I show you how to remove HTTP response headers in Windows Server and ASP.NET, after installing IIS using web.config files. This makes it a tiny bit harder for hackers and improves your server and website security. Stop giving hackers too much information.

Normal HTTP Response headers

Microsoft Internet Information Services logo
Microsoft Internet Information Services

Even though I'm not a big fan of security by obscurity (are you?), removing common server response headers is often advised by security experts. Attackers might gain a lot of information about your server and network, just by looking at the response headers a web server returns.

Therefore it's advised you remove at least some of these headers.

But let's start with how a normal HTTP HEAD response looks like:

HTTP/1.1 200 OK
Content-Length: 0
Content-Type: text/html; charset=UTF-8
Vary: Accept-Encoding
Server: Microsoft-IIS/8.0
X-UA-Compatible: IE=Edge,chrome=1
Date: Sun, 06 Jul 2014 10:05:34 GMT
Connection: close

Here you notice IIS displaying its version information in a Server header, as response:

Server: Microsoft-IIS/8.0

As with removing ETag headers in IIS, you can rewrite and empty the Server: HTTP response header in IIS with a URL Rewrite Module outboundRule.

Remove Server response header with an outboundRule URL Rewrite rule

In older IIS versions (IIS 7, 8.5, 8.0, 8.5) you cannot really remove the Server header. But you can rewrite its content and empty it. Here you use an URL Rewrite Module outboundRule to remove the web server version information from the Server: header response.

Use the following URL Rewrite Outbound rule for example:

<rewrite>
  <outboundRules rewriteBeforeCache="true">
    <rule name="Remove Server header">
      <match serverVariable="RESPONSE_Server" pattern=".+" />
      <action type="Rewrite" value="" />
    </rule>
  </outboundRules>
</rewrite>

What the outboundRule does is:

  • it looks for the header - or serverVariable - Server: in the output response stream, and rewrites the value with an empty string (nothing).

The end result is an empty Server: response header line:

HTTP/1.1 200 OK
Content-Length: 0
Content-Type: text/html; charset=UTF-8
Vary: Accept-Encoding
Server:
X-UA-Compatible: IE=Edge,chrome=1
Date: Sun, 06 Jul 2014 10:06:08 GMT
Connection: close

You've now successfully removed the Server version response from the HTTP headers!

This is a website-specific rule. If you want to create the rule for all of your applications, you have to create the rule at the server level. Also, some applications, especially third party applications, may require and depend on the Server header. Then you may need to remove this rule for those applications.

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Rewrite 'Server: Microsoft-IIS/8.0' with your own server information - just for the fun

The fun part of rewriting response headers is that you can display your own information string. For example, if you give in an value in the Rewrite action, that message is displayed:

<action type="Rewrite" value="Saotn Server Software systems, LTD." />
HTTP/1.1 200 OK
Content-Length: 0
Content-Type: text/html; charset=UTF-8
Vary: Accept-Encoding
Server: Saotn Server Software systems, LTD.
X-UA-Compatible: IE=Edge,chrome=1
Date: Sun, 06 Jul 2014 11:19:16 GMT
Connection: close

Isn't this fun, now is it? :)

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removeServerHeader requestFiltering in IIS 10.0

In IIS 10.0 (Windows Server 2022/2019/2016), you can remove the Server header by configuring requestFiltering in your web.config system.webServer node:

<security>
  <requestFiltering removeServerHeader ="true" />
</security>

In IIS Manager Configuration Editor:

Set removeServerHeader to True in IIS Configuration Manager requestFiltering node. You find this in the Internet Information Services Manager (of IIS Manager) tool.

Or using AppCmd.exe / PowerShell:

C:\Windows\System32\inetsrv\appcmd.exe set config -section:system.webServer/security/requestFiltering /removeServerHeader:'True' /commit:apphost
Set-WebConfigurationProperty -pspath 'MACHINE/WEBROOT/APPHOST/' -filter 'system.webServer/security/requestFiltering' -name 'removeServerHeader' -value 'True'

This way you don't have to fiddle with complex outbound rewrite rules. To remove ASP.NET's X-Powered-By header you still need the customHeaders section as mentioned below.

Verify setting removeServerHeader with PowerShell and AppCmd.exe

After setting removeServerHeader to True, it's recommended to verify this setting. In PowerShell you can use IISAdministration module, the output must be "True":

Get-IISConfigSection -SectionPath "system.webServer/security/requestFiltering" | Get-IISConfigAttributeValue -AttributeName "removeServerHeader"
True

With AppCmd.exe you have to look through the XML output:

c:\windows\system32\inetsrv\appcmd.exe list config -section:system.webServer/security/requestFiltering
<system.webServer>
  <security>
    <requestFiltering removeServerHeader="true">
<!-- ... -->

Remove ASP.NET 'X-Powered-By' header in IIS using web.config customHeaders

By default IIS tells the world it's powered by ASP.NET, by placing an X-Powered-By header:

HTTP/1.1 200 OK
Content-Length: 0
Content-Type: text/html; charset=UTF-8
Vary: Accept-Encoding
Server:
X-Powered-By: ASP.NET
X-UA-Compatible: IE=Edge,chrome=1
Date: Sun, 06 Jul 2014 10:07:37 GMT
Connection: close

This response header can be removed with a customHeaders setting in web.config, placed in the <system.webServer> node:

<httpProtocol>
  <customHeaders>
    <remove name="X-Powered-By" />
  </customHeaders>
</httpProtocol>

Remove X-Powered-By header with PowerShell:

 Clear-WebConfiguration -pspath "IIS:\\" -filter "/system.webServer/httpProtocol/customHeaders/add[@name='X-Powered-By']"

Now the X-Powered-By header is removed from the response header output

HTTP/1.1 200 OK
Content-Length: 0
Content-Type: text/html; charset=UTF-8
Vary: Accept-Encoding
Server:
X-UA-Compatible: IE=Edge,chrome=1
Date: Sun, 06 Jul 2014 10:10:02 GMT
Connection: close

X-AspNet-Version header

The X-AspNet-Version HTTP Header broadcasts to the world what version of ASP.NET is being used. Add the following content inside the <system.web> node in your application's web.config file:

<httpRuntime enableVersionHeader="false" />
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Last updated on 07/04/2024

48 Comments

    • Jan Reilink
      23/04/2021,

      Hi Ketan,
      What exactly did you do (configure in your web.config)? What did you expected it to do? And what was the result? If it’s not working working for you, and IIS still prints its name, then you did something wrong in your web.config file (there are different methods for different builds of Windows Server IIS), or you have some type of middleware intervening.

  3. chandu
    27/04/2020,

    Hi
    if i will send wrong request the server version is showing like below .

    HTTP/1.1 400 Bad Request
    Content-Type: text/html; charset=us-ascii
    Server: Microsoft-HTTPAPI/2.0
    Date: Mon, 27 Apr 2020 09:57:10 GMT
    Connection: close

    How to remove Server: Microsoft-HTTPAPI/2.0
    Content-Length: 334

  4. nikko
    07/04/2020,

    Hi,
    We’re using URL Rewrite Outbound rule to clear the value of the Server header and it works when using GET or POST, but when we use HEAD method is would still show IIS 8.5.
    Any ideas why? The only difference I see is that we’re not using “rewriteBeforeCache=true”. Could that be the issue?

    • Jan Reilink
      15/04/2020,

      Hi Nikko,
      Thank you for your comment.

      At this moment I’m not sure whether the outbound rewrite rule triggers on a HEAD request. Unfortunately, I’m lacking the time to look it up.

      The HTTP/1.1 RFC states for HEAD requests:

      The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response. The metainformation contained in the HTTP headers in response to a HEAD request SHOULD be identical to the information sent in response to a GET request.

      So it *should* produce the same output. But you could give https://forums.iis.net/ or https://stackoverflow.com/ a try for confirmation. I’m interested in the outcome.

  5. hamza Zuheri
    02/03/2020,

    I want to remove the text/html on response after sending the request to client as text/xml

  6. Avinash
    01/08/2019,

    Hi, How to remove the Response Server for the error 500?

  7. basavraj
    24/04/2019,

    Hello Jan,
    I am looking to implement this changes for my application which is running on windows server..
    Could you please help to share exact file name where I need to add above rewrite rule on window server
    reason why am asking as I have implemented same fix for removing server information for port 47001 and 5985 but this is something not working for 8080 port number. It was added in web.conf file and below is response message for 8080 port

  8. shailavb
    28/03/2019,

    amazing man thanks a lot!!

  9. Marq
    21/03/2019,

    Good day all, I am running into a problem: I succesfully created an Outbound Rule in IIS that rewrites the server header to “This is a Web Server” instead of Microsoft-IIS/7.5. However, after this the Active Directory Single Sign On is no longer working for the users. Is there another option that does not interfere with Single Sign On? It seems the server header is being used by Active Directory to authenticate. All ideas welcome!

    • Jan Reilink
      22/03/2019,

      Hi Marq! I’m sorry, but I wouldn’t know, I’m not familiar with Active Directory Single Sign On.

      Perhaps the renamed Server header doesn’t match the SPN anymore? You can verify SPN’s in your domain with setspn. And you can use tools like Chrome developer tools, fiddler, etc to view and inspect all header being sent and returned. (Edit: maybe you’ve renamed too many headers by accident?)

  10. Lonnie Ables
    12/02/2019,

    How do you remove-unwanted-http-response-headers if you’re using adfs 3.0 since it’s not using iis?

    • Jan Reilink
      22/03/2019,

      For as far as I know, you can only use a proxy in front of ADFS to remove headers.

  11. David
    26/09/2018,

    Thanks Jan. Great article i removed iis server headers successfully.

  13. Ankit
    07/09/2018,

    Hi,

    I am getting the Server Name as “Microsoft-IIS/8.5” even after rewriting the server name as “” in the Error pages. Following is the web.config code:

    • Jan Reilink
      07/09/2018,

      Hi Ankit,

      Unfortunately your web.config code got lost in the comment. But what do you mean with “in the Error pages”, like the default IIS error pages located in C:\inetpub\custerr\en-US? Or somewhere else? Perhaps you have to use existingResponse=passthrough too? See the other comments.

      • Ankit
        12/09/2018,

        Hi Jan,

        I am redirecting the error to the custom error pages like

        and I am using the following to remove/rename the Server Name:

        But, then also Server Name is coming in the custom error pages. How to remove the server name from the custom error pages?

        • Jan Reilink
          12/09/2018,

          Hi Ankit,
          Your code isn’t coming through, please use a gist if possible and link to there, or wrap your code nicely in `<code></code>` tags.

          • Ankit
            12/09/2018,

            Hi Jan,

            Thanks for the advice. I hope this time my code is visible.

            I am developing a mobile friendly application using MEAN. So. my issue is that I want to remove/hide/rename the Server Name from all the pages. I am able to do so in all the pages except the custom error pages. I am redirecting the error to the custom error pages like:

            and I am using the following to remove/rename the Server Name:

            But, then also Server Name is coming in the custom error pages. How to remove the server name from the custom error pages?

          • ANKIT
            12/09/2018,

            Hi Jan,

            Actually, the issue is that the server name is visible in the HTTP Headers. Using the outbound rule in web.config, the server name is removed from the web pages but it is not removed from the custom error pages to which I am redirecting. I have also used errorMode=”Custom” existingResponse=”PassThrough” but it’s still coming.

  14. Rikin Patel
    31/08/2018,

    When I used below code

    protected void Application_BeginRequest(object sender, EventArgs e)
    {
    var application = sender as HttpApplication;
    if (application != null && application.Context != null)
    {
    application.Context.Response.Headers.Remove(“Server”);
    }
    }
    Then I am getting following error.
    Error: This operation requires IIS integrated pipeline mode

    More Info: I am using IIS 10, website hosting as Application and Application pool as Classic mode. If I changed to Integrated mode then working fine. But right now I can not change to this on Production environment because it may create other issue.

    So, can you please suggest best solution in this situation.

    • Jan Reilink
      31/08/2018,

      Hi Rikin, thank you for your comment!

      I’m not a fan of Classic mode application pools. Why would you want to have IIS 6.0 behaviour? I’d say, fix the problems you have switching to Integrated mode, and move on from there turning off response headers. If Integrated mode is really not an option, try to use web.config settings to disable headers.

      HTH!

  15. Anonymous
    03/08/2018,

    Thanks for the help!

  16. Ron Hinds
    13/06/2018,

    I also have a rule that redirects http requests to https. But the redirect sends back all headers, including the Server: header. This is the http rule:

    This is from the Microsoft URL Rewrite reference page:

    Usage of a Redirect action implies that no subsequent rules evaluated for the current URL after redirection is performed.

    Is there any way to remove the server header on a redirect?

  17. Pablo
    15/11/2017,

    I am using IIS 8.5 and whenever I attempt to use in my web.config IIS does not like it. I’ve seen that this only works on IIS7 or other versions. Is there a workaround or other method to remove the ASP version?

    • Pablo
      15/11/2017,

      looks like it removed my code ” ” in my comment above

      • Pablo
        15/11/2017,

        one more try httpRuntime enableVersionHeader “false”

  18. Nishant
    05/09/2017,

    Removing the server variable from response using url rewrite outbound rules is not working . application is angular 4 application and My server is windows 8 with iis 8.5 and I have my web.config data as shown below .

  19. PRS
    12/12/2016,

    what is the impact,if application caching having both
    Custom HTTP Response Header +set common HTTP response header

  20. AErot
    15/09/2016,

    Hi, great article, but I’ve got question/problem..

    At the first glance all seems be well, I receive modified http headers, but when I send request to doesn’t exists page (and server will return 404 webpage) server name is ‘IIS 8.5’ in the HTTP headers..

    I found what is a problem – custom error pages.

    When I remove httpErrors elements from web.config, Server Name header isn’t display in HTTP headers (in both cases – correct/incorrect webpage url).

    How can I fix it ? (I want to have custom error pages and remove Server Name header..)

    Regards
    AErot

    • Jan R
      15/09/2016,

      Hi @disqus_E1570bwNoJ:disqus , thank you for your comment. Interesting… What are you using, PHP or ASP.NET, and which solution do you use to remove the Server: header? It might be a .NET Framework thingy.

          • AErot
            15/09/2016,

            Bullseye! It looks like it’s working with Passthrough :) I must think about error page in ASP.NET. Thx!

            Best
            AErot

          • Jan R
            15/09/2016,

            Nice find @disqus_E1570bwNoJ:disqus , if you have the relevant web.config lines for me (and the scripting language you use: ASP.NET, PHP or ASP), I can add it to this post. Thanks in advance!

          • Vijaikanth N
            24/09/2016,

            Hi,

            When i set the existingResponse=passthrough, the server information is not displayed for the 404 status code but my custom error pages defined in IIS stopped working. Is there any workaround for this?

  21. Ansonmus
    25/05/2016,

    We have tried it. But it doen’t work. Probably because of this line (MVC…): routes.IgnoreRoute(“{resource}.axd/{*pathInfo}”);

  22. Ansonmus
    25/05/2016,

    Thanks for the answer, do you have any idea how to fix this?

  23. Ansonmus
    25/05/2016,

    I’ve a issue with the solution.
    I can do a request to /blalbla.axd (every name possible) and then the “Server” variable will have a value…

    • Jan Reilink
      25/05/2016,

      Hi Ansonmus, thanks for your comment.
      The .axd file type is handled by the .NET Framework and often falls beyond the scope of URL Rewrite.

  24. oliverbill
    11/05/2016,

    This article was very helpful. The $2 donation is worth it.

  25. Kunal Maurya
    20/10/2015,

    Is there any way to completely remove “Server: Microsoft-IIS/8.0” from a site having static pages only like ?

    • Jan Reilink
      21/10/2015,

      Hi Kunal, thank you for your comment.
      An IIS Outbound Rule rewrites the output stream (HTTP response), so it’ll also remove the Server header from static HTML files.

Comments are closed