I'm working on IIS6, ASP.NET, VS2008. The web site uses a custom error handler to catch 404 errors and serve an alternate page. When presented with an url of the form:
http://srv/crimson/articles/index
Everything works perfectly. But an url of the form:
http://srv/crimson/blog.aspx
Where blog.aspx does not exist, fails with the following message:
Server Error in '/Crimson' Application. Description: HTTP 404...
When I try and debug, none of the breakpoints in my 404 handler are hit. So it appears that something is catching the request earlier. Where? And how to I get it to pass the request on to my handler?
Edit
Thanks to those who answered, but none of those ideas worked. I've decided to attack the problem another way.
You might wanna try this:
In IIS6:
open "properties" for your website
go to "home directory" tab
click on "configuration"
look for the extension ".aspx"
click on "edit"
check the checkbox which says "verify that file exists"
edit
And what about this:
http://msdn.microsoft.com/en-us/library/h0hfz6fc(VS.80).aspx
<customErrors defaultRedirect="sorry.htm" mode="On">
<error statusCode="404" redirect="NotFound.aspx"/>
</customErrors>
Since 'RemoteOnly' specifies that custom errors are shown only to the remote clients, and that ASP.NET errors are shown to the local host.
hmm, Assaf is right, but to add to his answer I need to post some code.
Yes, Assaf does mean something else ASP.NET offers it's own error handling, configured through the web.config. You can either manage this through the IIS Admin snap in, or directly in the web.config file.
Within the <system.web> element you should have:
<customErrors defaultRedirect="sorry.htm" mode="RemoteOnly">
<error statusCode="404" redirect="NotFound.aspx"/>
</customErrors>
You can configure a different page for each HTTP error code, or let the default redirect handle them all.
You'll find that you do indeed need to set these error pages up in both the IIS custom errors and the ASP.NET configuration, as otherwise you'll end up in this situation - some pages go to your 404, and others use a default that you've not customised.
You should also make sure that your custom 404 page actually returns a 404 header to ensure that search engines etc treat it correctly.
Response.StatusCode = 404;
Response.StatusDescription = "Not found";
ASP.Net has a custom errors configuraiton of its own.
Go to the ASP.Net configuration of your virtual directory (web application) and right-click -> ASP.Net -> Edit Configuration -> Custom Errors.
Maybe you got a 500 so redirect for 404 is not triggered. You may focus on this 500 error at first.
Related
I have Asp.net website (Webforms). I want to Display custom page for 404 errors. I have following entry in web.config file:
<customErrors mode="On" defaultRedirect="~/error.aspx">
<error statusCode="404" redirect="~/404error.aspx"/>
</customErrors>
But this only redirects all pages with extensions. But Extension-less URLs like [http://website/abc/123] are not considered as page request, therefore there's no mapping for 404 custom page display. Instead I get browser generated 404 error page.
I have also tried to use Global.asax file's Application_Error method, but this error doesn't fall in this method for this case.
Please suggest to capture such 404 exceptions.
Note: I have read the following Link that also discussed the simillar situation, but I couldn't understand the resolution for this. I want this to happen even with Visual Studio Debugging.
Thanks
Actually I had to put code for displaying 404 error in my custom URLRewrite module. Where I handled all extension less URLs & finally at the end where url has been checked for all cases, I rendered 404 Error page, as that url was not meant for my website.
Thanks
I've got this in my web.config and it's being hosted by the DiscountASP.net ISP
<customErrors mode="On" defaultRedirect="">
<error statusCode="404" redirect="404.aspx"/>
<error statusCode="500" redirect="404.aspx"/>
</customErrors>
I am hosting the site on DiscountASP.net and they also tell you to config it this way. I'm using Enterprise Library but I don't think that should make a difference. I don't believe I need to config anythign for a 404 in EL.
When my page loads with an error, my 404.aspx doesn't show and I get the default custom errors off message. I do not know why I don't get my 404.aspx page showing and get this instead:
Runtime Error
Description: An application error occurred on the server. The current custom error settings for this application prevent the details of the application error from being viewed remotely (for security reasons). It could, however, be viewed by browsers running on the local server machine.
Details: To enable the details of this specific error message to be viewable on remote machines, please create a tag within a "web.config" configuration file located in the root directory of the current web application. This tag should then have its "mode" attribute set to "Off".
Notes: The current error page you are seeing can be replaced by a custom error page by modifying the "defaultRedirect" attribute of the application's configuration tag to point to a custom error page URL.
Have you tried using a relative path to see if that makes a difference?
<error statusCode="404" redirect="~/404.aspx"/>
Alternately, try an absolute path:
<error statusCode="404" redirect="http://www.domain.com/errors/404.aspx"/>
EDIT: As others have pointed out, and based on your comment to another answer, the 404 error page should be displayed when someone navigates to a page that doesn't exist, whereas general errors on a page could be captured by the defaultRedirect. So if you're testing the 404 then make sure you're testing with a nonexistent page. To test the defaultRedirect then have one of your pages throw an exception etc.
Is it possible that you are overriding this in another web.config, say in a sub folder? Or we can go the other way. Are you sure this is in the application root?
Is there any reason why you don't want to use the defaultRedirect for 500 errors?
You are FTP-ing the files correct? Try uploading the file as a binary file instead of text. You might be suffering from an encoding problem. I'm willing to bet right now that nothing you are doing in your web.config is working.
I found a solution here.
The real catch was using this:
Response.TrySkipIisCustomErrors = true;
I'm having problems with handling URLS that do not exist...
In my development environment, I navigated to http://localhost:XXXX/FakeLocation and would catch the HttpException and handle it properly.
When I deployed to my production location, I'm getting a 404 error when I navigate to http://MyProductionURL/FakeLocation. How can I make the production location throw the HttpException so my code can handle it similar to how it works in my development environment?
ASP.NET will only handle file extensions it is registered in IIS to handle. So if the page was foo.aspx, then by default, ASP.NET returns the 404 page as set in the web.config. And by default 404 for foo.xyz will be handled by IIS because IIS handles anything that doesn't have a mapping.
This page shows how to set up wildcard mapping so that all requests, regardless to extension are handled by asp.net.
You probably need to configure IIS on the production location. The easiest thing you can probably do is
Go to the Control Panel, and under Administrative Tools open Internet Information Services (IIS).
Right-click on your web site to bring up the properties.
Go to the Custom Errors tab
Select to the 404 error and edit properties on it.
Change the Message Type to URL.
Set the URL to the page you want them redirected to.
you can do this in the custom errors node of the web.config
<configuration>
<system.web>
<customErrors defaultRedirect="GenericError.htm"
mode="RemoteOnly">
<error statusCode="500"
redirect="InternalError.htm"/>
</customErrors>
</system.web>
</configuration>
Msdn Reference
Looks like IIS handle this exception and does not pass error to ASP.NET.
Please check http://www.chat11.com/How_To_Setup_A_Custom_404_Error_Handler_In_.NET
I have a scenario in which I'm serving a file from codebehind.
which file, depends on request. in some cases there will be no file to serve and I want to return 404 to the browser.
how can I do that from codebehind? is this the correct course of action to show user there's no file available?
you can use the Response.StatusCode property to return a 404:
Page.Response.StatusCode = 404
As for the question of whether it's the "correct thing to do" I'd say it depends how the Page is going to be accessed. If you're going to access it programmatically then yes I'd go with the 404. If however it is going to be a user facing system, then I'd go with a custom page of some sort. Programs like codes and humans like more understandable things :-)
throw new HttpException(404, "File not found");
I'd be more inclined to redirect them to a custom error page that clearly indicates that the file cannot be found, in the style of the rest of your web application.
You can specify how to handle certain errors in web.config
<customErrors mode="On">
<error statusCode="404" redirect="FileNotFound.aspx"/>
</customErrors>
I toggled customErrors=On in web.config, set the defaultRedirect for my custom Error.aspx page. However, this is only to prevent application errors from spitting out code - I'd still like IIS to handle 404s etc. with its default handlers, since they work fine.
Any way to specify in my ASP.NET app or IIS for IIS to take priority?
I know I could add the formatting in my Error page...but I'd just be replicating what exists in IIS.
It didn't tried it (I don't have visual studio on that box) but maybe if you set your customErrors to handle only error 500 (server error), that'll work. Just a guess.
Let me know if it works
You can do it in the web.config file
<customErrors = "On">
<error statusCode = "404" redirect = "route_name"/>
</customErrors>
Don't forget to register the route in the Global.asax.cs