I use the MVPS hosts file. I have a program called HOSTS secure that automatically checks for updates of the hosts file. It also keeps my hosts file locked, so I do not use Spybot to lock the hosts file.
When MVPS releases a new hosts file, HOSTS secure downloads the update, unlocks my hosts file, updates it, then locks the updated hosts file.
However, every time HOSTS secure locks the hosts file, Spybot sets itself to lock the hosts file too, even though I do not want it to do this. I usually forget that this happens. Then the next I go to update the hosts file, my update gets interupted because Spybot has the hosts file locked.
So it appears that HOSTS secure and Spybot have a conflict.