I run Bitdefender Antivirus Free Edition. There are no events, quarantines, or exclusions noted for NoMachine files or processes.
I don’t use hard-drive encryption.
I’m using the default Windows Defender firewall, with private network exceptions allowing NoMachine Client, NoMachine Device Server, NoMachine Display Monitor, NoMachine Node, NoMachine Player, and NoMachine Server. See attachment.
I’ve uninstalled NoMachine, rebooted, reinstalled NoMachine, rebooted, set debug logging, and tried starting the server again. NoMachine reports “Server running”, but no process is listening on port 4000 (confirmed with netstat -an) and I get a connection timeout when attempting to connect to the server from a remote client instance.
If I click into Server preferences > Services on the affected machine, the NX service says it’s stopped. I can start it, but this makes no difference to netstat output or to client connection attempts, and the next time I check it, it shows as stopped again. The Service logs > Export button has no effect; I can select a directory, but no files are saved there.