I've had the exact same problem as this guy
I had a LOT of custom entries in my HOSTS file, including a lot to get rid of ads, but in the past couple of days I've noticed I am seeing ads again, so I looked in my HOSTS file, and the only entries are for localhost and Unchecky, as much as I liked it, and it seems to work, if it's destroying my HOSTS file, I have no choice but to uninstall it!!
There isn't a backup of the HOSTS file at all, and I'm not sure I have a recent one myself, I hope you don't just dismiss this like the other guys, and actually have a look, obviously it's a REAL BUG, and causing REAL PROBLEMS, could you at the least attempt to work out why, rather than just dismiss it because of "a lack of feedback", not that I can think of what else could be added. If you need I can include a copy of the hosts file since it's now very short ...
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