Now, back to RSTS/E discussion. So I thought i'd try out Ersatz-11 instead of simh. I've gotten RSTS/E + DECnet installed alright, and it attaches to the interface fine and it seems to work better. But every time I try to SET HOST I get some variation of: Event type 5.15, Receive failed Occurred 22-Oct-25 13:36:28.1 on node 33.306 (GEWT1) Line UNA-0 Failure reason =Unrecognized frame destination Ethernet header = AA0004003285 3C075443A176 0800 and Event type 0.0, Event records lost Occurred 22-Oct-25 13:39:13.0 on node 33.306 (GEWT1) Any ideas? Looks like you're trying to access your host from an emulator which couldn't set correct mac address. Are you using (Apple?) WiFi adapter? ... or simh incorrectly built for BSD/OSX...