Hello everyone. Basically, I know what these words mean, "until now" and "up until now" but I have got a question: what tense do we usually use with those 2? For example, when I want to say that I hadn't known about something before someone told me about it. Should it be: "I have had no idea about it until now" (now I know of course) or "I had no idea about it until now" (now I know)? Please, help.