>Yep. Again, if the question of who's using the file is being asked from an Admin account, it isn't a problem. The question becomes how do you know which accounts are the correct administrators before making the option to look at the information available to the user within your application.

Here comes my NTControls Library and gives access to all info about users and groups.

>Yes, but AFAIK, there's no easy way to include a group in a trusted domain in the group of a trusting domain; the individual users have to be made members of the trusting domain's groups.

I believe global groups on a trusted domain can be members of of local group on the current domain. Certainly, this is not like any group type member of any group and this is a drawback IMHO.

Vlad