Elle, thanks for linking to that useful thread! ernyoka, while it is true that Poser itself makes no use of Interlok, if you install SR2 before starting Poser, I simply don't know whether the boot sector writing was already done during the initial install of the original Poser CD (if you have a CD prior to SR2). NOTE: even if it was, it is almost certainly harmless, as long as the Interlok software never gets fired up. What I mean is, lets give Curious Labs a break here. Everything is probably A-OK now that they've stopping using Interlok. The "two drives" thing is more of a "passing thought", based on my experiences prior to SR2. Forget I said it. But yes, since talking about "boot sector", that means two PHYSICAL drives. And to reiterate: I don't know whether the boot sector writing occurs during initial CD installation, or the first time a Poser 5 (if PRIOR to SR2) is fired up - in which case you're certainly safe.