Welcome to Microsoft http://www.microsoft.com/
Microsoft Windows Family http://www.microsoft.com/windows/
The NT logo program has information about how programs should use the registry.
Frank Condron's World of Windows News
The All Windows Information Page
Dylan Greene' Windows 95 Starting Pages
The NT BugTraq archive and other topics
Hobbit's paper on cifs security problems
Jim Frost's papers including NT file system security
NT vs. UNIX Network Security study
Somarsoft's Windows NT Security issues. Somarsoft makes various utilities for NT such as DumpACL.
C2Net Software, Inc has some notes about their products, some of which use SSL and they used to host the hackmsoft page.
Microsoft has also released a short note about NT security concerns regarding SMB and HTTP. In short their response is to use proxy servers and firewalls for now :( However they have a longer white paper about their future security plans. This is a pretty good high-level discussion of NT 5.0 security - lots of stuff about the directory and fine grained access control, Kerberos 5 as the default, SSL/PCT for Internet stuff, and a couple of things about DCE and RPC.
This white paper describes how SSPI APIs can be used directly, as well as through other application interfaces, such as DCOM, secure RPC, WinSock 2.0, and WinInet.
This guide to Securing Windows NT Installation appears like it might be useful. It includes descriptions of a number of registry settings.
More NT papers from MS.
R. C. Consulting maintains the NTBugTraq list and archive but also has a number of links to NT security related topics.
SAMBA the main distribution site.
Virtually UNIX for the UNIX centric NT users.
A variety of Win32 links including the GNU project.
TUCOWS The Ultimate Collection of Winsock Software.
Virtual Software Library at oakland.edu
Winsite (Software Archive for Windows)
European Windows NT University Support Centers
A skimpy view of Microsoft's ftp site.
Third party tools that MS has been tracking
PowerProfiler for NT from SystemSoft
Windows NT Magazine had an article on the subject in the Macrh 1997 issue.
Paperbits is a site with lots of third party device drivers for NT.