At moon111:
Such a device might be neat for "standard" users, but most likely useless for my purposes.
I prefer having full access to all data at anytime, so deactivating an hdd on boot wouldn't be of any use for me (I do have an internal sata backplane tho, connected to an 8port controller, but that ain't bootable).
Besides it only supports PATA devices from what I read, and my current rig only contains SATA HDDs.
As for the usual testing of operating systems I use virtual machines, which, as you might know, are also completely separated from the host OS.
I'm almost sure that the error occurs due to the handling of the "System Volume Information" Folders containing the drive letter assigned by windows. Now this might be fixable by accessing/rewriting it from Knoppix or any other (preferably live) boot OS, but for a product such as Vista, which costs quite a lot of money and gets advertised to be the next-generation OS, I would expect it to be as userfriendly as possible, which ultimately includes an easy-to-use and freely configurable bootloader.
Then again I might have been just unlucky to run into these issues, but at least those show some rather unknown, yet imo important weaknesses of Vista.
~D][A