Reference VelocityDB

I have need to write data into VelocityDB. For this purpose I referenced libraries which are used by this DB. But when I execute code, I'm getting following error message:

Updated with TypeInitializationException: The type initializer for 'VelocityDb.Session.SessionBase' threw an exception.

Here is the code:

public static void AddToDb(string addToDbStringBuy, string addToDbStringSell)
        {
            using (SessionNoServer session = new SessionNoServer("d:\\VeloDB\\"))
            {
                session.BeginUpdate();
                var domData = DomArray.Parse(addToDbStringBuy, addToDbStringSell);
                session.Persist(domData);
                session.Commit();
            }
        }