Comment 3 for bug 239782

What do you mean with switched off? Switching off the disks with the Windows partitions or not setting a mount point for the partitions.

Which installation system did you use? The graphical (on the live cd) or the text based (alternate)? IIRC you cannot set the real time clock to use local time or UTC (in graphical installation). Where did you set in GNOME to not use UTC? The only way I know to disable UTC is to set it in /etc/default/rcS.

Some reasons for using UTC by default: http://www.cl.cam.ac.uk/~mgk25/mswish/ut-rtc.html