If you install OS/2 2.0 on an OS/2 Extended Edition system, the base operating system files will be replaced. OS/2 2.0 does not replace the Extended Edition components (such as Communications Manager). You will need to upgrade these components to products (now sold separately) that are compatible with OS/2 2.0. You can upgrade to Extended Services to restore Communications Manager and Database Manager functions. You can upgrade to LAN Server 2.0 to restore LAN Requester and LAN Server functions.