AI CS6 Won't Open!

I own and use AI CS6. I upgraded to AI CC 6 months ago but have stopped the subscription now. My problem is that AI CS6 wont open today. It opened last night for me but today it just keeps going to an AI CC window and says I need to upgrade my subscription. I don't want to upgrade my subscription. I want to use the AI CS6 that I bought and paid for several years ago! Why won't it open today???? Rrrrr!