Originally posted here by gauravjulka
No doubt *Nix OSes are more secure as compared to the WIdows because of the Open source factor.
*nix generally refers to Linux, BSD, and all unix derivatives (Solaris, AIX, et. al.). Only two of those bases are open sourced. Open Sourced software also does not necessarily corrolate to security, though it is conducive to catching severe mistakes.

It is harder to hide viruses in the code for *nix OSes. Windows is provided by a single party Microsoft, the so called giant inthe software biz. It is its own sole responsiblity to fix the bugs which remain in their software. But for *nix there is no one responsible out there for bug fixing issues. If there is someone out there, Then do drop a message about it.
Actually there are. The various linux distributors take on that responsibility when they charge you for the operating system.

But administration in Windows 2000 is more sophisticated because of Windows Active Directory Services. Does any *nix system has any equivalent to this thing.
NIS+. Or now, Netware on Linux I suppose.

The beauty that this costly OS has in it its marvellous support over the network. Integration of various security mechanisms in one wonderful framework called Windows Active DIrectory Services.
Yes, they've almost managed to catch up to 10 year old Netware technology.

No. of applications don't count for the usefulness of an Operating System. Consider them when it comes to ease of use, user friendliness, sole responsibily for the professional creators for any bugs. So windows provides all that. Keep in mind that upto this point Windows is many step ahead of other OSs. The need is there to make it a bit open sourced so that even the amateur programmers can also tweak the bugs for themselves
There isn't a need to open the source of Windows, I don't know on what basis you think this is the case. Amateur programmers are part of the problem with software in general, and that discussion is better left for a software development discussion targeting bad development practices in general. Check the General Programming Questions and Programming Security forums' histories for such discussions.

Originally posted here by AngelicKnight
A true expert can harden any OS by mastering it. A Windows expert can harden his OS as well as any Linux distro; conversely, a Linux user with no understanding of his OS can render it far weaker than Windows. In the end, security is defined by the man behind the machine, not the kind of OS he's running.
This applies up to a point, but falls apart when you consider that after a certain point, there is more security capability on Linux than there is on Windows. To my knowledge there is no included in the OS method of jailing a process using chroot-style wrappers/technology.
Windows also opens itself to vulnerabilities by tying so many extraneous applications into the OS. How many IE vulns have to be classified as an operating system vulnerability because of its ties to the OS? The same is not true of most other OSes.

At a baseline the statement is correct, but you will eventually hit a wall where Linux can do many security-related things that Windows can't.