yes, due to shifting access paradigms, find full text sometimes doesn’t work as it should. When it happens, it is best to let Thomson know the journal name, and they try to identify the problem. I find saying it here in the forum is often best, as Tech support usually trying to tell you what you already know and tried.
Right now, Cell isn’t working for me, while Nature is. I believe they know there is a problem, and are working on it. Which Journals/publisher sites are you having problems with?