Abstract: Systems and methods are provided for defining a default handler software application in response to an event at a computer. An event, for example, a user opening a file with a specific extension or accessing a uniform resource locator (URL) with a specific protocol, may trigger the operating system to instantiate a user-level default handler program associated with the event type and the specific user. Users may define user-level default handlers through a centralized user interface maintained by the operating system. During the application installation process, an application may register lists of supported events that the application is capable of handling.

Abstract: A platform supports an unmanaged secured workgroup, without a server, for common user access and secure resource sharing among the computers in the group. User accounts are synchronized by replicating and modifying the accounts at each computer of the unmanaged secured workgroup. A computer advertises a change in account information to other computers in an unmanaged secured workgroup. If one of computers in the unmanaged secured workgroup determines that the change is not reflected in the current account information, the computer requests the updated account information from the advertising computer. Any conflicts between user accounts at different computers are resolved before synchronizing the user account in the unmanaged secured workgroup. Also, an application program interface (API) enables an application to query properties of a networked computer system and an unmanaged secured workgroup and to join the unmanaged secured workgroup.

Abstract: System(s), method(s), and/or technique(s) (“tools”) are described that enable a user to permit multiple tasks requiring elevated rights with as little as one rights elevation. For example, the tools may enable an installation wizard operating within a limited-rights context to perform multiple tasks that require a higher-rights context with a single rights elevation by the user. The tools may do so using an object agent, an instance of which may be created by the installation wizard following a single rights elevation. This instance of the object agent then creates instances of other objects without requiring that the user elevate his or her rights. These other objects' instances may then run the tasks that require the higher-rights context.