I'm a bit unclear on TrueCrypt's hidden volume protection. When I mount an outer volume with hidden volume protection, I get a stern warning not to write to the hidden part of the outer volume (contiguous at the end of the outer volume, I believe). This is an odd restriction, since my OS chooses where to write things, and I can't specify what sectors to use! Does the hidden volume protection actually prevent my OS (Win7 / WinXP on different machines) from writing to those sectors? Or does it just warn me if I try to write to them, in which case the changes to the outer volume are not saved? If that's the case, of course, the "protection" of the hidden volume comes at the cost that I will lose data to the outer volume if I try to write to the hidden sectors. Since Windows reports the whole size of the outer volume available -- whereas half of it should be hidden -- I believe this is the case. If that's true, it seems that using outer and hidden volumes is not really reliable. Any comments? Am I missing something? thanks.