[Kazun]

http://msdn.microsoft.com/en-us/libr...(v=vs.85).aspx - Specifying the Search Scope

Base. A base search limits the search to the base object. The maximum number of objects returned is always one.

One-level. A one-level search is restricted to the immediate children of a base object, but excludes the base object itself. This setting can perform a targeted search for immediate child objects of a parent object. For example, consider a parent object P1 and its immediate children: C1, C2, and C3. A one-level search evaluates C1, C2, and C3 against the search criteria, but does not evaluate P1. Use a one-level search to enumerate all children of an object. An IADsContainer enumeration translates to a one-level search.

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