Tricky Custom 404 URL Problem

Here's a challenge I'm having trouble finding an answer for:

Running IIS5 on a W2k Server on our dev box.
On there is a website which uses a custom 404 file, set up as a URL in the custom errors section of IIS.
The 404 file is meant to use a server.transfer to mimick the existence of non-existent pages (for SEO purposes), taking the Search Engine friendly URL and transferring processing to the appropriate real, parameterised page. This transfer and page content stuff all works OK. The problem is that the URL is meant to appear in the browser as, for example:

http://<devbox>/foo.asp
instead, it appears as:
http://<devbox>/<ourcustom404file>?404;http://<devbox>/foo.asp

Does anyone know if there's an IIS setting we can alter, or somesuch in order to have the URL present as http://<devbox>/foo.asp?
The annoying thing is that this functionality seems to work on other people's servers who have bought the same software (the website is an off-the-shelf third party application, but they have apparently never seen the behaviour our dev box is displaying).

Input greatly appreciated!

No input on this one? Somebody has to know!
Please do make a post if it rings any bells with you.


"Ewen" wrote:

 > Here's a challenge I'm having trouble finding an answer for:
 >
 > Running IIS5 on a W2k Server on our dev box.
 > On there is a website which uses a custom 404 file, set up as a URL in the custom errors section of IIS.
 > The 404 file is meant to use a server.transfer to mimick the existence of non-existent pages (for SEO purposes), taking the Search Engine friendly URL and transferring processing to the appropriate real, parameterised page. This transfer and page content stuff all works OK. The problem is that the URL is meant to appear in the browser as, for example:
 >
<font color=purple> > <a style='text-decoration: underline;' href="http://<devbox>/foo.asp</font" target="_blank">http://<devbox>/foo.asp</font</a>>
 > instead, it appears as:
<font color=purple> > <a style='text-decoration: underline;' href="http://<devbox>/<ourcustom404file>?404;http://<devbox>/foo.asp</font" target="_blank">http://<devbox>/<ourcustom404file>?404;http://<devbox&g...foo.asp</a>>
 >
<font color=purple> > Does anyone know if there's an IIS setting we can alter, or somesuch in order to have the URL present as <a style='text-decoration: underline;' href="http://<devbox>/foo.asp?</font" target="_blank">http://<devbox>/foo.asp?</font</a>>
 > The annoying thing is that this functionality seems to work on other people's servers who have bought the same software (the website is an off-the-shelf third party application, but they have apparently never seen the behaviour our dev box is displaying).
 >
 > Input greatly appreciated!
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