If you are getting kicked with an error message that "This Steam account does not own this game," be aware that this is not a problem with the SunLit servers.



It is some sort of problem with Valve's Steam network. It is happening to users all over the place, including CS:S servers.



There does not seem to be anything either players or server operators can do to fix it.



There's a thread about it over on the steam forums, so I'm sure Valve is aware of it and working on it. You can find more info here [2].