PC>  PFILEFINDBUF3     pffb          = malloc( FF_BUFFSIZE );
 PC>  PFILEFINDBUF3     pff;

Try instead PBYTE pfb;

 PC>      pff = pffb;

pfb = (PBYTE)pffb;

Also:  pffb = (PFILEFINDBUF3)pfb;

Think carefully about what happens when you increment pff vs.
incrementing pfb.  In fact, a little test program containing this might
help clear it up:

  PBYTE        pfb = NULL;
  PFILEFINDBUF pff = NULL;

  printf("\npfb + 1 = %p\npff + 1 = %p\n",++pfb,++pff);

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