in reply to Dir Create

In a word, as previous responders noted, "permissions."

Now what I hope may offer some added value, rather than a mere echo:

I have observed (at least in several governmental organizations I'm familiar with) windoze admins do their setups with a default !allowed for file or dir creation in the root. My impression is that they're trying to force users to confine their writes to "Documents and Settings"\usename in some misguided attempt at "enhancing security."

Sometimes, they get carried away with this kind of procedure and apply it where it shouldn't be applied.