It might be a problem with Windows XP/drivers, because you get an error and then the icon disappears. So what probably happens is that while the data is being transmitted windows makes an error, then WinHIIP/HDL_Dump has no choice but to report an error. If it was WinHIIP/HDL_Dump causing the error, it would be highly unlikely that the HDD would get disconnected.
Now that you have the game put on the HDD, try to upload it again through your computer with a different name without deleting the old one. That way you can figure out if there was a bad sector that caused it.
BTW, where did you get your IDE-USB adapter from and for how much? I think I'm going to get one of those so that I can transfer files easily.
US/NTSC V5 - Matrix Infinity v1.75. - Network Adapter - WesternDigital 80GB HDD - CodeBreaker v9.2