UPDATE: I solved this issue. The hard drive had plenty of errors (failing) but this program called HDD Raw Image was able to clone my external drive onto another one and the Wii U recognized it and let me copy my most precious data (didn't bother with data that I don't care about.) I might run into problems later though if the data is corrupt.
Link: http://hddguru.com/software/HDD-Raw-Copy-Tool/
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Turned on my console today and noticed a red X next to my Download List. An error is displayed for every game on the list. This error code, 105-0321, is not listed on Nintendo's website, and there are almost no Google search results. This forum post will be the most documentation it has (I think).
Turns out my USB hard drive which has worked fine for a couple years suddenly isn't being recognized. It won't show up in Storage Settings, and all games and game save data that were on it are now simply gone. All my virtual console games, eShop games, save data, etc. have vanished. Anything on the internal storage is fine... which is basically just Super Smash Bros.
If this were any other console, this would not be a big deal for the following reasons:
1) On Wii, there are ways to back-up save data easily, and even back-up entire games.
2) On PS3 and 360, you can back-up save data to the cloud, to USB storage, to a computer, etc.
3) On Xbox One, save data is always backed up to the cloud automatically. On PS4, 1 GB of save data can be automatically backed up.
4) On Nintendo 3DS, saves are on the cartridge, and you can relatively easily back-up save data.
Now, there is probably some way I could've backed up save data on the Wii U, but it wasn't easily apparent. I've heard that you actually have to back-up the entire game to another USB hard drive (you can't just back-up save data by itself?), but obviously it's too late for this so it doesn't matter to me.
OK, whatever, this wouldn't be so bad if I could do one thing... use other people's save data.
If I could download saved data online from other users for games like Tokyo Mirrage Sessions (which I'm never gonna play again if I have to redo like 30 hours), then this would be a minor inconvenience to me. I'd stick their save data on a SD card and make do with the fact that it's better than nothing. Only problem is, Wii U cannot do this -- you cannot use any save data other than your own. All data is locked to your console, so you can't share save data.
So, I've determined that there's nothing that can be done if my hard drive is the problem. To discern if it is, I've taken these steps:
1) I changed from the back USB ports (yes, I'm using USB Y-Cables) to the front USB ports. Nothing.
2) I've restarted the console, left it on for a while, etc. Nothing.
3) I've plugged the hard drive into my Windows computer. Nothing appears -- expectantly, because it's formatted to Wii U's special formatting. However--the drive does show up in "Device Manager." It also lights up and is clearly on; makes noise, etc.
4) I've connected another hard drive to the Wii U and the system prompts to format it, so the Wii U itself can still detect hard drives.
5) I've changed hard drive cables. Nothing.
[For those wondering it is a Western Digital My Passport 500 GB with a USB Y Cable (a USB cable that has two ends so it can be powered properly by the Wii U. It's important to note that this isn't the problem because even hard drives without USB Y cables will still initially be recognized by the Wii U. This hard drive cannot be recognized at all.)]
Conclusion?
Given that other hard drives can be recognized (even those without Y cables or external power), something must be wrong with at least the Wii U and this specific hard drive; or the hard drive itself.
I could re-format the hard drive in Windows and see if the hard drive works then -- and if it does, that would mean the hard drive wasn't at fault. But I don't want to do this just yet until I'm sure there's no way I can save my precious Wii U data.
Next steps
I'll see if anyone here has any ideas.
My Wii U is out of warranty so I'm not keen on sending it to Nintendo only for them to tell me there's nothing that can be done. To be clear, everything else on the Wii U works, and I can still re-download my games etc. (although Wave Race curiously doesn't give me an owner's discount for transferring my Wii license years ago while everything else does...maybe unrelated).
Other than that, I will have to accept the fact I will never play some of my games again because I don't have the patience for it, and I don't want this to happen again.
Link: http://hddguru.com/software/HDD-Raw-Copy-Tool/
----
Turned on my console today and noticed a red X next to my Download List. An error is displayed for every game on the list. This error code, 105-0321, is not listed on Nintendo's website, and there are almost no Google search results. This forum post will be the most documentation it has (I think).
Turns out my USB hard drive which has worked fine for a couple years suddenly isn't being recognized. It won't show up in Storage Settings, and all games and game save data that were on it are now simply gone. All my virtual console games, eShop games, save data, etc. have vanished. Anything on the internal storage is fine... which is basically just Super Smash Bros.
If this were any other console, this would not be a big deal for the following reasons:
1) On Wii, there are ways to back-up save data easily, and even back-up entire games.
2) On PS3 and 360, you can back-up save data to the cloud, to USB storage, to a computer, etc.
3) On Xbox One, save data is always backed up to the cloud automatically. On PS4, 1 GB of save data can be automatically backed up.
4) On Nintendo 3DS, saves are on the cartridge, and you can relatively easily back-up save data.
Now, there is probably some way I could've backed up save data on the Wii U, but it wasn't easily apparent. I've heard that you actually have to back-up the entire game to another USB hard drive (you can't just back-up save data by itself?), but obviously it's too late for this so it doesn't matter to me.
OK, whatever, this wouldn't be so bad if I could do one thing... use other people's save data.
If I could download saved data online from other users for games like Tokyo Mirrage Sessions (which I'm never gonna play again if I have to redo like 30 hours), then this would be a minor inconvenience to me. I'd stick their save data on a SD card and make do with the fact that it's better than nothing. Only problem is, Wii U cannot do this -- you cannot use any save data other than your own. All data is locked to your console, so you can't share save data.
So, I've determined that there's nothing that can be done if my hard drive is the problem. To discern if it is, I've taken these steps:
1) I changed from the back USB ports (yes, I'm using USB Y-Cables) to the front USB ports. Nothing.
2) I've restarted the console, left it on for a while, etc. Nothing.
3) I've plugged the hard drive into my Windows computer. Nothing appears -- expectantly, because it's formatted to Wii U's special formatting. However--the drive does show up in "Device Manager." It also lights up and is clearly on; makes noise, etc.
4) I've connected another hard drive to the Wii U and the system prompts to format it, so the Wii U itself can still detect hard drives.
5) I've changed hard drive cables. Nothing.
[For those wondering it is a Western Digital My Passport 500 GB with a USB Y Cable (a USB cable that has two ends so it can be powered properly by the Wii U. It's important to note that this isn't the problem because even hard drives without USB Y cables will still initially be recognized by the Wii U. This hard drive cannot be recognized at all.)]
Conclusion?
Given that other hard drives can be recognized (even those without Y cables or external power), something must be wrong with at least the Wii U and this specific hard drive; or the hard drive itself.
I could re-format the hard drive in Windows and see if the hard drive works then -- and if it does, that would mean the hard drive wasn't at fault. But I don't want to do this just yet until I'm sure there's no way I can save my precious Wii U data.
Next steps
I'll see if anyone here has any ideas.
My Wii U is out of warranty so I'm not keen on sending it to Nintendo only for them to tell me there's nothing that can be done. To be clear, everything else on the Wii U works, and I can still re-download my games etc. (although Wave Race curiously doesn't give me an owner's discount for transferring my Wii license years ago while everything else does...maybe unrelated).
Other than that, I will have to accept the fact I will never play some of my games again because I don't have the patience for it, and I don't want this to happen again.