I got that message quite a while back on something I made that had just disapeared from my inventory. I hate that it gives the user this message without saying that it's their system that ate the items at least.. This should send a message to the creator or something so we know that someone has actually lost something.
I was really frustated when I got that thinking "Here's our next epidemic." When we started selling shoes so long ago they were copy, no transfer and you'd be amazed how many people didn't like their shoes.. We changed them to no copy/transfer and so many more people were suddenly happy with their shoes. We had a handful come in and buy after we had changed and within a day said they hated them and we would say "o.k. give them back we'll give you a refund" and they'd said "No.. They're no transfer, just give me my money back." After being informed they were transfer now they suddenly weren't so bad and 9 out of 10 didn't want their money back anymore.
I have great customers 99% of the time but when the scams start it goes into epidemic proportions fast.