Read-Only Error when Rendering a .mpg file to D: drive

I am certain that this is something simple I have missed, but I am rendering
an .mpg file from Sony's Vegas Studio to the D:\ drive (and/or several
different folders/subfolders) in D:\ and keep getting the Read-Only message
from XP and the program. I attempted to send to my C:\ drive and it would
have worked except for file size constraints. I have tried to change the
attributes to match (hopefully not doing irreparable harm), and I just can
not get it to work.

Any help would be greatly appreciated!
--
NATC
''Need Answers for the Technologically Challenged''