My husband died and had credit cards under mine name without my knowledge. Am I responsible for paying the creditors if I didn't sign for the cards?

First its not a good idea to piggyback your question on someone else's. This can lead to confusion. You should start a new thread. So I've moved your question to its own thread.

This may depend on whether you are in a community property state or not. In a community property state, debts incurred by one spouse can be attributed to the other. It also depends on how your husband opened the account. If he opened them as joint accounts and signed your name to the apps, then he may have committed fraud. If he opened them with you as an authorized user, then you probably are not liable.

Yout first need to pay any debts from the estate. If the estate doesn't cover all the outstanding debts, try paying the ones you are named on first. Any others you can send back the bills marked deceased and see what happens.

For them to collect from you, they will have to prove you are liable.