That's a very general question, and I'd need to know more of the facts to give you an answer.  You should discuss this with a lawyer in your area, and one place to look for an attorney is our website, http://attorneypages.comIf you posted the notice to inform someone, maybe a tenant of the unit, that you had started eviction proceedings, and they are saying they never saw the notice, you might at least in theory have some grounds to sue, and there might be special laws dealing with this as a misdemeanor as well.  The biggest problem that usually comes up in a case like this is proving who did it.