Error Handling URLS that do not exist - asp.net

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

Related

ASP.NET MVC handles 404 errors differently on local IIS and when deployed to Azure

I have a controller where an action returns a 404 error on ASP.NET MVC. Working locally, I get the page with 404 error correctly. When I deploy it to azure, instead of the page, I only get a text-only page:
The resource you are looking for has been removed, had its name changed, or is temporarily unavailable.
I've tried all three values on on customErrors mode in web.config (mode = Off, On, RemoteOnly) and it doesn't seem to change anything at all.
Why is Azure behaving differently on 404 errors and how can I make it behave the same as local IIS?
Okay I've found out the problem. Apparently, it wasn't even hitting the ASP.NET's custom errors handler, and was being caught at server level.
I've played with web.config and added this:
<httpErrors errorMode="Detailed">
<remove statusCode="500"/>
</httpErrors>
It now passes my error to the ASP.NET's custom error handler correctly.

IIS ARR overrides application custom 404

I have several web servers and the proxy based on IIS ARR to balance the load between the web servers.
If user goes to not existing page web server returns custom "notfound" page with 404 status code (works correct if I do not use proxy) Unfortunately it has been overridden by the ARR and I see IIS standard 404 screen instead of returned from web server (as on picture http://i.snag.gy/v1xvY.jpg).
Does anyone know how this the overriding can be avoided to allow users see the custom 404 page?
Thanks in advance
Add
<httpErrors existingResponse="PassThrough"/>
to your web.config file. It should look something like this:
<configuration>
<system.webServer>
<httpErrors existingResponse="PassThrough"/>
</system.webServer>
</configuration>
If you're developing an ASP.NET application, put it in the application's web.config file, not the proxy's.

404 handling - Difference between local ASP.Net (C# 4) and remote server (live)

I'm facing a problem:
I do want to do URL rewriting with ASP.Net
It works perfectly using my local settings, but once on the server it doesn't work as expected.
Local
Request to /unavailable-file.aspx gets well in the Application_Error (Global.asax.cs) and then is being redirected to /404.aspx
Request to /unavailable-random-folder or any other file gets well in the Application_Error (Global.asax.cs) and then is being redirected to /404.aspx
Remote
Any request to a .aspx file WILL be catched in the Application_Error
Every other request (.jpg, folder, etc...) will NOT be catched at all and thrown into the default 404 page error
My problem:
Yesterday I was installing my new website to the server and I saw that Application_BeginRequest was not even fired AT ALL on my server, when it was every time (for every file or folder requested) in my local computer (with visual studio).
I had to create an HttpModule and now I am successfully getting the events firing... but not for non .aspx requests.
Everything seems to be bound on the URL : when it ends with .aspx it's correctly managed and when it's not, it's just not managed at all.
What should I do to catch every Application_BeginRequest even for non aspx page?
I have that in my web.config to try to force the 404 errors into my page:
<customErrors mode="On"
defaultRedirect="404.aspx">
<error statusCode="404" redirect="404.aspx"/>
</customErrors>
But as I said, as long as it's not a request ending with .aspx it's not being redirected and I get the default ASP.Net 404 error.
(My host is "reliablesite" if it can help, and I have the settings of the 404 errors pointing to my 404.aspx page inside the manager (shared hosting), it does not change anything)
I wish everything would work as in local mode.
If you have any tip on how to resolve that problem let me know.
In the development web server every request is handled by the aspx engine, as that's all there is. In the live server different file types are handled by different engines.
To make the live server use the aspx engine for every request you have to change the configuration in IIS for the web site.
Related: ASP.net web.config doesn't catch all 404's
The solution of this problem is given here when you have a shared environment:
Active the ASP.Net Integrated Pipeline in your shared environment settings (a thing that is available since IIS 7)
Add this to the web.config:
<system.webServer>
<modules runAllManagedModulesForAllRequests="true">
<add name="RedirectHttpModule" type="RedirectHttpModule" />
</modules>
</system.webServer>
Where RedirectHttpModule is a custom module handling Application_BeginRequest for example.
The "runAllManagedModulesForAllRequests" means that all managed modules will be invoked for all requests to web application.

Possible to use customErrors=On, but only for non-IIS handled errors?

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

IIS 404 Custom Error not working as expected

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.

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