There's an Emprex help forum but it seems there's no company engineers involved; it's merely a bunch of people who possess the item and who seek to help fellow-sufferers by sharing experiences and advice. A bit like a victim support group, for people who have been beaten up in the street!
Reading the forum pleas for assistance make me wonder whether the product is poorly designed and well built, or excellently designed and badly built. Of course, it might be badly designed and badly built, for all I know. I certainly won't buy an Emprex product again, for as long as I live.
Clearly, a good tip before buying a product is to look on the Internet and see what level of support there is. Search for Emprex complaints, or something. Had I done my homework before paying out good money, I wouldn't have gone ahead.
Still no word from Emprex themselves, so I'm now reformatting the hard drive. It's a bit drastic, but sometimes a completely fresh start is the best solution.