A Windows NT computer can connect to standalone LAN Manager 2.x servers and LAN Manager 2.x servers participating in a LAN Manager 2.x domain. LAN Manager 2.x and Windows NT computers interoperate because they both use server message blocks (SMBs) to communicate between the redirector and server software. The NetBEUI Frame (NBF) and TCP/IP protocols used by Windows NT are also interoperable with NetBEUI and TCP/IP protocols written for LAN Manager 2.x.
Note LAN Manager 2.x servers can act as backup domain controllers in a Windows NT Server domain. Both local and global user accounts are replicated to LAN Manager 2.x servers acting as BDCs. Because LAN Manager 2.x does not support trust relationships or local groups, a LAN Manager 2.x server can never be a primary domain controller.