How does the registry modification work for hijacking Outlook’s COM objects?

The attack sets a `TreatAs` value for the first COM object (CLSID `{84DA0A92-...}`) to redirect calls to a second COM object (CLSID `{49CBB1C7-...}`). The second object's `InprocServer32` key points to the attacker’s DLL, with a `ThreadingModel` of `Apartment`. Similar techniques are used in other COM hijacking scenarios, such as Hijack CAccPropServicesClass and MMDeviceEnumerator and Hijack explorer.exe.