COM OBJECT AND MANAGED CODE OBJECT INTEROPERABILITY

Communicating between managed add-ins and COM hosts. A computing environment includes host objects which may be one of a COM object or a managed code object. The computing environment further includes add-in objects implemented in managed code. Add-in object can provide additional functionality to the host objects. A method includes acts for communicating between add-in objects and host objects. The method includes determining that a first host object to be communicated with is a COM object of a COM host. As a result of determining that a host object to be communicated with is a COM object, incoming and outgoing communications from a managed code add-in are routed through an interop proxy. The interop proxy is implemented in managed code with a managed code add-in. The interop proxy is configured to translate managed code invocations to COM code invocation, and to translate COM code invocations to managed code invocations.