As I mentioned in my earlier comments: I was the one who edited your question and removed the windows-server tag.
The main reason for that was that the tag popped up in the new tags overview and as EEAA explained it doesn't really improve upon the well-used version specific tags such as windows-server-2012 windows-server-2008-r2 etc.
Afterwards I converted it to a synonym for the generic windows tag, which already has the following recommendation in the tag-description which is also quite relevant for the Windows Server family operating systems :
Windows is the brand name for a series of operating systems from Microsoft. Instead of tagging a post "Windows", try to use a more specific tag, like windows-7, windows-xp or windows-server-2008-r2
