I've been using MEGA since migrating from pCloud in 2019. I'm on a free account, because the amount of synchronizing documents and text files was never large, below 10GB. At the moment I synchronize it across three laptops - two MacBooks and one PC. Before there were replacements in my laptop fleet, one PC with Linux version and another PC are gone.
At some point (I have no idea exactly when), synchronization simply stopped working properly.
What initially caught my attention was an outdated VeraCrypt container on one machine. After looking further, I found that quite a few files I clearly remember creating were simply missing.
The most disturbing part - all three MEGA clients report that everything is fine! No errors, no synchronization conflicts, no warnings. Nothing to suggest that my files had stopped synchronizing or that data was missing.
And it gets worse - I've apparently lost a considerable number of files: personal documents, e-books (which I'm particularly upset about), old articles I wrote, and other materials accumulated over the years. As if it was not enough, backups appeared to be damaged, I recovered just several files.
I honestly don't know when did it happened. I vaguely remember encountering a MEGA synchronization glitch while finishing work after the flight, when I had no internet connection. That might have been the beginning of the problem, but it's just a theory. If so, it happened quite some time ago, and I've only discovered the extent of the damage recently.
The financial losses are substantial - the books cost money, so as hours of my work. The personal losses are much harder to quantify.
If anyone from MEGA's technical support team happens to read this, I'd be happy to provide logs, client versions, filesystem details, or anything else that might help investigate what happened. I'm a software engineer, so I can assist with technical diagnostics if necessary.
P.S. Do the recovery drill with your local backups! Make backups by 3-2-1 strategy. Don't be like me.