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#21
I have no idea. Very flimsy description of what he did, if you ask me.
And besides, there's an awful lot of important stuff going on in those "first bits" of the drive. It's obviously impossible for him to have conceivably have known what was really going on.
Plus, although I haven't installed or run this WD diagnostics utility it clearly warns that YOU WILL LOSE YOUR FILE SYSTEM AND DATA. It doesn't say you might... it says YOU WILL. How much stronger of a warning can you read that implies this to be a complete low-level format of the entire drive. I can't imagine there is any selectivity.
Yes, there seems to be an option for (a) Quick Erase, and (b) Full Erase, but without reading the README or instructions/documentation I don't know how the program works. But it's only reasonable to believe that this is a complete low-level FORMAT of the entire drive, and you'd lose EVERYTHING on the drive. Assume that is true. Now, if you want to preserve some data that's currently on the drive you'll need to back it up somehow first, so that you can restore it after the low-level FORMAT zeroes out the entire drive. If you have no backup/restore capability that can guarantee you won't lose any data on this drive, then don't consider any of this as remotely possible. It's just not possible... if you have irreplaceable data on this drive and cannot backup/restore it.
So, again... his comments are "wacky" to me, and I'm sure there's more to the explanation for why his drive suddenly began holding on to the drive letter across boots. But it IS your exact problem, so it's worth at least thinking about what makes his story similar to or different from yours.
You haven't explained where this second WD drive came from. Was it brand new as part of all the new equipment you bought when you built your new PC? Was it a replacement for an older drive? How did it get formatted for use in your new PC from out-of-the-carton? Did you just assume it was usable, or did you initialize it in some way?