Looking for information to secure .Net in a hosted environment

I've just installed .Net 1.1 and upgraded to 3.0 on my W2K3 server and I
want to lock down ASP.Net so that my hosted users can't see each others
folders on disk. The disk is already secured via NTFS with separate user
and anonymous accounts for each hosted customer. But I don't want ASP.Net
to run as the "ASP.NET" user - I want it to run as a different user per
customer that I specify.

Can anyone point me at some documentation on how to do this?



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