You don't need to dump NAND, you know. That's a depreciated thing. If you're actually using an EmuNAND, that might well be the source of your woes. You should probably just try running Mocha without anything like that.MOCHA-CFW...the whole NAND to SD dumping process.
Apologies for the necrobump but I'm running into the same problem and the above solutions didn't work for me. I followed the guide at wiiu.hacks.guide exactly and I am receiving the "Please only connect or disconnect USB drives..." error after CBHC autoboots into the system menu. I have a USB 2.0 HDD which uses a Y splitter in the rear USB ports.
Did you just get the y cable or has it worked before? If it's never worked, it could be that it still is not giving the hard drive enough power and you may have to try a different one.
Are you using RedNand or just regular SysNand?
The problem seems to usually be associated with trying to use RedNand from everything I've read. The OP was also trying to use RedNand. If you are don't, just use SysNand. If you're not, then IDK.
Hi. Where is this config file located? Cannot seem to find. Cheers