Html - IIS 7, .Net 4: Server Cannot Append Header After HTTP Headers Have Been Sent?
May 19, 2010
I am getting the following warnings on the Event Log for a Asp.Net WebSite running on IIS 7.
Exception information:
Exception type: HttpException
Exception message: Server cannot append header after HTTP headers have been sent.
at System.Web.Hosting.ISAPIWorkerRequest.SendUnknownResponseHeader(String name, String value)
[code]....
I tried to debug the WebSite but it just does not show in debugger. The web page which has got this issue contains the following.
Its a content page with a Master page.
It has a grid inside an UpdatePanel which is Triggered by a Timer.
On the specified time grid data is refreshed.
Everytime this happens we see a new warning in the EventLog.
I am creating a web application in C#.When my page loads I fire an asynchronous thread to process some data. Part of this processing is the updating of a cookie. However when I save the cookie to the response by System.Web.HttpContext.Current.Response.Cookies.Add(c) where c is the HttpCookie, I get the following exception:HttpException: Server cannot modify cookies after HTTP headers have been sent.
We have a basecontroller that has both an OnActionExecuting and OnActionExecuted. Occassionally, the OnActionExecuted will throw an exception 'Server cannot modify cookies after HTTP headers have been sent.'. This doesn't happen all the time, and we can't find a pattern to it. My guess, based on searching, is that filterContext is not always the current context. Is there a way to rewrite the Cookies.Add to get the current context, always? Or is the fact that we are in the ActionExecuted mean the headers will always already have been sent and we shouldn't be doing anything like this in the executed step?
I have an ASP.Net site (happens to be MVC, but that's not relevant here) with a few pages I'd like cached really well.
Specifically I'd like to achieve:
output cached on the server for 2 hours.if the file content on the server changes, that output cache should be flushed for that page cached in the browser for 10 minutes (i.e. don't even ask the server if it's that fresh)when the browser does make an actual subsequent request, I'd like it to use etags, so that the server can return a 304 if not modified.
(note - time values above are indicative examples only) 1) and 2) I can achieve by Response.Cache.SetCacheability(HttpCacheability.Server) I know 3) can be achieved by using max-age and cache-control:private I can emit etags with Response.Cache.SetETagFromFileDependencies();
but I can't seem to get all of these things to work together. Here's what I have:
can browsers do both 3) and 4) like that? When Firefox issues a new request after it expires in the local cache, it does indeed send the etag the server responded with before, but I get a 200 response.setting the variables like above, where would I set the duration of the output caching?
I am trying to make ActionFilter which redirects banned users to /Error/NoAccess site, so I have ActionFilter:
[Code]....
Before each public class xxxxxxController : Controller I use [NoBannedUsersActionFilter]. But for example on website /Account/LogOff I have error: 'Server cannot modify cookies after HTTP headers have been sent.' and VisualStudio shows me AccountModel.css file and this method:
---- Server did not recognize the value of HTTP Header SOAPAction: http://tempuri.org/GetBestBidOfferData.
The odd thing is that I have several methods in this webservice, and only two of them got me the error message. It used to work, but then gave me the error message after i added some other methods to the asmx file.
The namespace should be the same for all the methods. One more thing to note is: these two methods had return data type DataTable before, and I changed it to DataSet. It should not affect anything, I assume.
I have created one page to show the progress of payment . After successful payment i need to redirect user to the payment confirmation page. When i am redirecting am getting the following error.
Cannot redirect after HTTP headers have been sent.
HTTP 502 Proxy Error - The size of the response header is too large. Contact your ISA server administrator. (12216) Internet Security and Acceleration Server
I am guessing it has to do with the size of hidden "__ViewState" tag in my ASP.NET pages.
I also realize that this is restriction imposed to by IT on the users end and I have no contol over it.
I disabled ViewState on all the controls in my ASP.NET pages. However, __ViewState is still generated very large (as always) to persist control-state (e.g. checkbox, radiobutton, etc.)
In my application I need to set a http response header. I'd like to do this in web.config. but I dont'know if this is possible and I can't find it on Google. Solution Finally, after a long search I found the solution. Create a class with this code:
public class myHTTPHeaderModule : IHttpModule { #region IHttpModule Members public void Dispose() { } public void Init(HttpApplication context) { context.EndRequest += new EventHandler(context_EndRequest); } void context_EndRequest(object sender, EventArgs e) { HttpResponse response = HttpContext.Current.Response; response.AddHeader("Content-Language", "*"); } #endregion }
(Don't ask me why to use this event, but it works..) Now add a line in web.config in the HttpModule section:
I Have a specific set of HTTP response headers I'm trying to recreate in ASP.NET. Here is how it looks in Fiddler (Raw):
HTTP/1.1 200 OK Content-Length: 570746 Content-Type: audio/wav Last-Modified: Wed, 19 May 2010 00:44:38 GMT Accept-Ranges: bytes ETag: "379d676ecf6ca1:3178" Server: Microsoft-IIS/6.0 X-Powered-By: ASP.NET Date: Tue, 05 Oct 2010 18:35:18 GMT
Here is how it looks on the Headers tab (same data. Different view)
I am trying to recreate the same set of headers (different values of course) with code, on an ASP.NET page. The biggest problem is with the cache settings and the ETag. It usually shows some "private" or similar cache setting and no ETag value, even though I'm trying to set it explicitly with
This has been bugging me for a while now. Whenever I try to share my website link on Facebook or another link-sharing site, the link-sharing site either removes the URL (like it doesn't recognize it as valid) or in Facebook's case - it can't retrieve meta-data automatically.
I'm pretty sure that it used to work. However, Googling / StackOverflowing for this problem is a difficult task, since I have no idea what possibly could create this problem.
I've tried to create a static .HTM file on my website, and that works fine: test.htm
My default home page is a classic ASP (yeah I know, PHP version in the works) which uses IIS 7 URL Rewrite module.
I've tried to check the resultcodes and headers for both test.htm and my default home page on this page: [URL]
This is the results:
test.htm
URL=http://www.orango.nu/test.htm Result code: 200 (OK / OK) Content-Type: text/html Last-Modified: Fri, 04 Feb 2011 10:16:55 GMT Accept-Ranges: bytes ETag: "0d877a654c4cb1:0" Server: Microsoft-IIS/7.0 X-Powered-By: ASP.NET Date: Fri, 04 Feb 2011 10:40:08 GMT Content-Length: 452
default home page /
URL=http://www.orango.nu Result code: 200 (OK / OK) Cache-Control: public Content-Length: 13463 Content-Type: text/html; Charset=UTF-8 Accept-Ranges: bytes Server: Microsoft-IIS/7.0 Set-Cookie: ASPSESSIONIDSCSADCAR=DLPBECCBGDJMADLEPMOMHDDC; path=/ X-Powered-By: ASP.NET Date: Fri, 04 Feb 2011 10:24:22 GMT
Scrollable GridView with Fixed Headers inside ASP.Net UpdatePanel using jQuery Plugin. I have one more question in that. How to adjust the width of the columns headers because for some of my gridviews the headers not showing the proper format. in the gridview I gave HorizontalAlign="Left" and in the columns I gave
I am having doubt in whether to use string or string builder to append html elements like "div" and others in my page in mvc. Is there any other approach for this thing.
I have an ASP.NET content page. The HTML tag associated with the content page is declared in the master page. I need to add an attribute to the HTML tag from the content page. My problem is, I do not know how to access this HTML tag from the content page.
We are implementing a single sign on mechanism in an enterprise environment, where the token is shared between applications using HTTP header. Now, in order to do the integration test, I need to write an application to simulate this. Is there any way in ASP.NET where I can redirect to another web-page and pass a custom HTTP header in the process?
On the client side I have a form: <form ... action="www.link-to-another-domaint" > <input type="hidden" id="asd" value="fgh" > .... </form> <script type="text/javascript"> document.forms[0].submit(); </script>
Then on the other domain - there is also my other application - I'm trying to get the hedaer "key" by this code:
Request.Headers["key"].ToString();
But there is no such header. Is there is a desicion? Where is my mistake?
Is it at all possible to use IIS7's rewrite capability in web.config to strip a particular HTTP header from a client request?We have an application that makes an HTTP POST to our website, and apparently the request contains the HTTP Expect header. Previously this was not a problem, but we've switched hosts and now the site is returning HTTP error 417 Expectation failed. So the real solution is to fix the software so it doesn't send the Expect header, but that can't happen soon enough for the folks in charge, who'd like to come up with an immediate web-based fix.I've used ISAPI_Rewrite before and I've read that it can strip a header, and the new host claimed they had ISAPI installed... but that seems to have been a lie, as I cannot get it to work, and support's only response on the subject is "use IIS7 Rewrite instead."
I have one ajax call web service, and want to add some http headers using javascript, can we do that use setrequestheader in ms ajax?This is my javascript
I've tried to write my own HttpModule (IHttpModule) that adds a Header like that:
public class MyModule: IHttpModule { public void Init(HttpApplication c) { c.BeginRequest += delegate{c.Response.AddHeader("MyHeader", "MyValue");}; } public void Dispose(){} }
I have a very simple query. I have added custom header to my website. Now I want to read the custom header. I am using IIS 6.0 on windows XP. I have already tried using using the Request.ServerVariables and and Request.header method. But none of them give me the custom header added to website.
First, a little background. I have written a custom HTTP compression module for ASP.NET. My development machine has Windows 7 Ultimate, which comes with IIS7. My production environment uses IIS6.
The problem I'm having is, Resource Expert Droid (redbot.org) tells me that I need to add a header to my response to properly support compression: "Vary: Accept-Encoding"
On IIS7 in integrated mode, it works properly. However, in classic mode, which is how my application ultimately runs, I cannot get my code to output this header using any of Response.AppendHeader(), Response.Cache.SetVaryByCustom(), or Response.Cache.VaryByHeaders.
