From Longman Business Dictionary
incompatiblein·com·pat·i·ble /ˌɪnkəmˈpætəbəl◂/ adjectiveadjCOMPUTING computers, computer systems, or programs that are incompatible cannot be used togetherincompatible withMost PCs in Japan run on software based on NEC Corp’s architecture, which is incompatible with IBM machines.