Microsoft operating systems are defective products. They should not be used in environments that require high security.
Sorry, but you can replace 'Microsoft operating systems' with Linux, Solaris, HP-UX, IRIX, AIX, FreeBSD, OpenBSD (barely! OpenBSD is pretty solid), MacOS, IPSO (barely!) and the statement would still be just as true. Again, they are all tools. In the hands of the proper craftsman (ie, someone how knows how to secure them), they are fine. In the hands of a cluebie (majority of sysadmins/server admins/desktop admins/network admins) then you have what we've experienced for the last 10 years.
The big problem is that we as a society have been conditioned to be compliant with those who ask things of us (we give out info easily and freely).