ASP.Net and CustomError Handling

[Guest]

I have written a custom dll that I put inside the /bin directory of a
production IIS server. Inside the config file of the web application i have
added the following setting:

<httpModules>
<add name="ExceptionManagerHTTPModule"
type="Digiscribe.HTTPModule.ExceptionManagerHTTPModule, HTTPModule" />
</httpModules>

In this dll I have inherited from the IHttpModule which in turn has given me
the ability to trap unhandled exceptions and errors through out the
application. Everything is working great. If an error happens that has not
been handled then this module kicks in and does what I need it to do.
However, on all 404 errors it decides not to work and directs it to a generic
error page "The Resource cannot be found".

When I was working with this application on my local box 404 errors were
handled by my custom dll, once moved to production on a different server,
they are no longer handled. Any help in figuring this out will be greatly
appreciated. Thank you in advance.

Sincerely,
Paul ><>

 

[Joyjit Mukherjee]

Hi,

try putting a customerrors element in your web.config as follows: -

<customErrors mode = "On" defaultRedirect = "YourDefaultErrorPage.aspx">
<error statusCode = "404" redirect = "Your404HandlerPage.aspx" />
<customErrors/>

HTH
Regards
Joyjit

 

[Frank Mamone]

Hi Joyjit,

This will work, but not as intended. Paul wants his custom exception handler
to take care of the error so he can do custom stuff.

I too am curious on why this is not working.

-Frank

 

[SevDer]

I think the result is obvious.
And Joyjit's suggestion is a solution.

It doesn't work for 404 pages becuase your dll is for your web
application, however page 404 is IIS behaviour. Therefore it never
reaches your application when page is not found and as a result it
doesn't load and process your dll. If you need 404 to process your dll,
then you need to refer this in web.config custom error pages as Joyjit
suggested.

 

[Frank Mamone]

SevDer,

I think you're on the right track but then as stated earlier, the custom dll
will not pick it up.

Maybe you need to disable the 404 default handling in IIS.

Paul maybe you can check the Custom Error tab in IIS on your development
server and see how the 404 is set?

- Frank