How to tell if your sim got hacked. Well usually the signs are obvious. Missing items, White items, even possibly 100's of scripts missing. How do they do it? Simple. Viewers like hydrastorm and darkstorm have options such as God mode override hack, which let's the user become a god on your land. The viewers also can let someone delete items from your sim, clone items, and even take the scripts. Well that's fine, you say, my opensim blocks hydrastorm and darkstorm. Except these viewers have a feature that lets them masquerade as regular firestorm, singularity, hippo, and others... It tricks your simulator into thinking the person is not using hydrastorm, but is instead using firestorm. But there are other hacks as well, the reverse friend permissions hack, sim crashers, and more. So what's a good defense? Some packages like dreamgrid, include an option to autobackup when you like. And keep N number of backups before recycling them. Dreamgrid also makes it easy to back up your inventory to an IAR. I suggest you use features such as these, or if you're on linux, learn to save your oars from the command line, as well as your iar's. While hackers can and often do use a vpn to gain access to a sim they plan to attack so their ip cannot be traced. For example PIA (private internet access) gives their users thousands of servers to choose from, with many different IP addresses. So blocking by ip address is nothing more than a temporary snafoo for hackers. If you block by name, they come back with an alt. Also there's a setting in opensim that allows a grid owner to edit the attachments of people that come to their grid, and it's trivial to turn this feature on. To sum it up, some people are just jerks, and all you can do is backup, backup, backuppppp.