Okay it seems I have found a slight clue what's going on. I've tested the front two ports on the wii u. The left one works, the right one has the exact problem as the back's top one. What I'm thinking according to my multiple tests is that my USB (Patriot Rage XT 64GB 3.0) uses more power than the average USB. It is possible that each pair of the Wii U's ports have one that has slightly lower power supply than the other one. I don't know if this is true, but I've used a USB adapter + 4gb SD (on the one that's not working in the back) and it worked fine. Any clue if this is true?

 

The thing is, the USB flash stick works no problem with one of each two ports. It also has no problems with multiple computers/laptops i've used.

 

Thanks, I actually ordered a y cable for my hdd. One thing I'm wondering is if what I am saying is true. I do have my doubts, but having the same exact results for both pairs are a bit too good to be coincidental don't you think? Has anyone else experienced the same problem I did? It is quite possibly unique to my usb, as I have only tested with two different ones.

 

One thing I'm worried about is that port 0 (top back port) is one of the lower powered ones. If I remember correctly, USB loader GX only recognizes hard drives from that port.

 

Im currently having similar issues with my Western Digital Elements 500gb HDD. In all of the wup installers many games wont install to my USB drive, they reach a certain percentage, then there is a click sound, then the installation just freezes, sometimes it will allow me to back out to HBL but sometimes it will crash or give black screen with error code - cant recal the code right now but will update post when I see it again. They install to nand fine just not USB. Also I am unable to tranfer the games installed to nand to USB in data management - says software could not be trasfered. Saying that I have successfully installed 7 or 8 games to USB (most came via uTikDownloadHelper). What is confusing is that most of the games that wont install to USB do install to my nand - an work correctly. I havent tried the Y-cable because why did it all me to install the games that are on the USB now, it never crashes when playing them. I have also tried turning off the USB HD sleep setting via data management menu (down on d-pad whilst holding + an -) this didnt seem to make a difference. I have the same issue across all 4 USB ports.
I am interested to see if anyone else out there has had this problem and if they managed to resolve it. Could it just be bad roms or is it my HDD? Im using Haxchi and Mocha, that is all wii u CFW I have used so far. Or could it be to do with the games ticket? I dont know what I am doing with tickets and sign patching - is this something I need to learn for brazillian method booting for Wii U games, Dlc and Wii U Eshop titles downloaded from wii USB helper? Im a bit lost in it all ha