mask/hide browser url header after redirect.

Tried it but doesnt seem to work at all. The page totaly errors out and gives a server error. i'v been looking at samples on dev central. What your your recomendation be? is it a problem because of the way the redirect url formated? due to auditing I have to hide the true path, or is does this have to be fixed on the server?.. Is there a way to save the url are a variable and then just replace it? Im also asking the Web Developers if about the concerns you brought up.