reference my post above, you cannot change permissions on a windows box by ftp. You have to either be able to assign the remote drive and change permissions that way or have the host switch the permissions for you.
Hence the "contact the mother ship" comment.
While you are doing initial install, it should not be giving you a can't write error. If it is, you will need to get the host to change the permissions and I'd leave them alone until you're sure you've got the settings correct.

I don't want to get into a "my os can whup your os" battle here, but now that we've established a need to at least for now use windows, how's about working just a little more on helping? I worked several stores very well from IIS BUT>>>
I had control of the drives and could set permissions.

Yes, you can rock and roll with Linux but, sometimes you gots to take what you gets.