It is finally time to remove all traces of an ancient protocol that is a security sinkhole: NTLM. You may not recognize it, and you may not even know that it is in active use across your networks. But the time has come for its complete eradication. The path won’t be easy, to be sure.

The acronym is somewhat of a misnomer: it stands for Windows New Technology LAN Manager and goes back to Microsoft’s original network server operating system that first appeared in 1993.

NTLM harks back to another era of connectivity: when networks were only local connections to file and print servers. Back then, the internet was still far from a commercial product and the web was still largely contained as an experimental Swiss project. That local focus would come to haunt security managers in the coming decades.

In this analysis for CSOonline, I recount its troubled history, what Microsoft is trying to do to rid it completely from the networking landscape, and what enterprise IT managers can do to seek out and eliminate it once and for all. It will not be a smooth ride to be sure.