DCOM was also amazing, in how much surface area it exposed to the network. Random COM objects which were never intended to be called remotely, and were poorly s

DCOM was also amazing, in how much surface area it exposed to the network. Random COM objects which were never intended to be called remotely, and were poorly secured, could be exposed by accident. So in the infamous Windows XP SP2 (not a major release of the operating system, but a mere service pack), DCOM got locked down hard. If you have a legitimate use for DCOM (like an OPC-DA server), you have to toggle several obscure settings to make it work again (see https://www-bd.fnal.gov/controls/opc/Using_OPC_via_DCOM_with_XP_SP2_v1.10.pdf https://www-bd.fnal.gov/controls/opc/Using_OPC_via_DCOM_with... for a fourteen-page tutorial).