I have tried every permutation of Admin privilege and Compatibility mode.

Every time the installer accepts my key says where do you want to put this?
(It defaults to my D: drive for some weird reason)
- yes I have tried express install too
- yes I tried removing D:

I have:
Win 7 x64 (latest SRVC pack)
over 500 gigs left on my 1.65 Tera drive (c:)
over 50 gigs on my 192 gig (d:)

yet every time I hit go...

"Insufficient disk space"

Yes, I have looked elsewhere first. I have not found anyone with this problem before.
Some even specifically stated 'installed fine'.

Umm... Help?

Are you installing from CD?

Make sure you have writing priv's to the drive your trying to install it on.

Installing from CD, Have full blown Admin privileges on every folder and write privileges on every folder (even system).

A friend reports that sometimes games have problems with drives over a certain size.
I don't think DS2 is in that category.

Can anyone else confirm it doesn't?

Give GPG-Servo a pm about this here ~ ucp.php?i=pm&mode=compose&u=18790
he will defo beable to tell you more and possably fix it for you.

Update:

I have my DS2:BW working now.

I installed on another machine (XP if you care).
Then copied the directory over to my computer.
I then applied the solution to allow BW to work with the steam version of DS2 (Reg editing to identify the install directory to BW)

The rest is history of Aranna.