IFWXSessionFilter interface

Applies to: desktop apps only

The IFWXSessionFilter interface exposes a method that the Microsoft Firewall service can use to send notifications about events that the filter is registered to handle in a specific user session. Each user session may have a different combination of session filters attached to it. However, each session filter is attached to a single user session.

An instance of the session filter object is created for a user session when the Firewall service calls the IFWXFilter::AttachToSession method.

This is the interface typically used for attaching a data filter to a user session.

For more information about how the IFWXSessionFilter interface is used in application filters, see Filter Object Model.

For more information about implementing the IFWXSessionFilter interface, see Implementing a Session Filter Object.

When to implement

Every application filter must implement this interface to receive notifications for events in a user session and to react to these events.


The IFWXSessionFilter interface inherits from the IUnknown interface. IFWXSessionFilter also has these types of members:


The IFWXSessionFilter interface has these methods.


Detaches the session filter from its session. This method should release all references that the session filter object holds on the session and any related objects.


Notifies the filter that the Microsoft Firewall service detected an event related to the user session to which the session filter is attached.



Minimum supported client

None supported

Minimum supported server

Windows Server 2008 R2, Windows Server 2008 with SP2 (64-bit only)


Forefront Threat Management Gateway (TMG) 2010



See also

Filter Interfaces



Build date: 7/12/2010

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