Windows Update Agent (WUA) uses the enumerations that are listed in the following table to represent the status of operations.

AddServiceFlag Defines the possible ways in which the service registration can be processed.
AutoDownloadMode Defines the logic that is used to determine whether Automatic Updates will automatically download an update once it is determined to be applicable for the computer.
AutomaticUpdatesNotificationLevel Defines the possible ways in which elevated users are notified about Automatic Updates events.
AutomaticUpdatesPermissionType Defines the possible ways to set the IAutomaticUpdatesSettings::NotificationLevel property or the or the IAutomaticUpdatesSettings2::IncludeRecommendedUpdates property.
AutomaticUpdatesScheduledInstallationDay Defines the days of the week when Automatic Updates installs or uninstalls updates.
AutomaticUpdatesUserType Describes the type of user.
AutoSelectionMode Defines the logic used to determine whether a particular update will be automatically selected when the user views the available updates in the Windows Update user interface.
DeploymentAction Defines the action for which an update is explicitly deployed.
DownloadPhase Defines the progress of the download of a current update that is returned by the IDownloadProgress::CurrentUpdateDownloadPhase property.
DownloadPriority Defines the possible priorities for a download operation.
InstallationImpact Defines the possible levels of impact that can be caused by installing or uninstalling an update.
InstallationRebootBehavior Defines the possible restart behaviors for an update.
OperationResultCode Defines the possible results of a download, install, uninstall, or verification operation on an update.
SearchScope Specifies the variety of updates that should be returned by the search: per-machine updates, per-user updates, or both. Per-user updates are updates designed to affect only a single user’s environment. For more information, see IUpdate4::PerUser.
ServerSelection Defines the update services that Windows Update can operate against. .
UpdateEndpointAuthTokenType Defines the type of tokens that can be used for authenticating with an endpoint.
UpdateEndpointType Defines the type of endpoints that can be used to connect to a service.
UpdateExceptionContext Defines the context in which an IUpdateException object can be provided.
UpdateLockdownOption Defines the functionality that the Windows Update Agent (WUA) object can access from Windows Update.
UpdateOperation Defines the operations that can be attempted on an update.
UpdateServiceOption Defines the options to remove the service registration for a scan package service.
UpdateServiceRegistrationState Defines the possible states for an update service.
UpdateType Indicates whether an update is a software update or a driver update.