Re: Lock layer OR other layer (if name is different)

you'd be fine with just doing this (below) -- since your layers' names are already known to you.  The function puts the get-by-names into a try{}catch{} so that the script won't error-out when a name isn't found:

function test(){    function tryLockLayer(name){        try{            lrs.getByName(name).locked = true;        } catch(e) {            return;        }    };      var doc=app.activeDocument;    var lrs = doc.layers;    tryLockLayer("Artwork");    tryLockLayer("Graphics");    tryLockLayer("Info");  
}


test();

also if the layers other than Info are ones you want to lock, you can just loop and lock layers whose names are not "info"