Also known as the magic worm (hi Dark Stalker, StoneHead) the protection that HMVS uses is quite clever 'cos it checks the first 16 kBytes for the instruction sequence of mov si,SI_MAGIC mov di,DI_MAGIC they're encoded as 0BE,x,y,0BF,u,v where x,y,u and v are the magic values. when HMVS finds 0BE and 0BF separated by two bytes from each other then it calls INT3 with the supposed magic values (the INT3 handler is a simple IRET, so no problem should arise if SOFT-ICE is not installed). and guess what happens when HMVS finds the traces of the loader part of SOFT-ICE in that low memory area...