Changing domain user password

I've been searching around for an answer to this question, but haven't
gotten too far. I'm fairly new to ASP.NET, so I'm not sure how to setup
machine.config and web.config properly.

What I want to be able to do is allow a domain user to change their password
in the AD via a webpage. We have several users with domain accounts, but
they do not actually login to our domain as they are spread out all over the
country. I have a VBS script that notifies them when their password is due
to expire, starting 10 days out.

Since these users are not local to where my domain controller resides, they
have to call me or email me to have their password reset. I found an
example written by Ryan Dunn using an Impersonate function that he wrote
(www.dunnry.com), but I keep getting an error stating: "Parser Error
Message: The XML file
c:\winnt\microsoft.net\framework\v1.1.4322\Config\machine.config could not
be loaded. Either a required impersonation level was not provided, or the
provided impersonation level is invalid. "

This seems like, to me, a fundamental type of function to do, but info on
how to do it is all over the place. Does anyone have any good ideas or
steps on how to accomplish this?

Thanks for any help,
Harry


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