Why wont my 1990 cadillac deville start from the solenoid switch or with the key?

i tried to start it with the key. nothing happened ,so i got a jump nothing happened. i tried to start it from the starter and solenoid switch. then it started but cut right back off.Why wont my 1990 cadillac deville start from the solenoid switch or with the key?You may have problem with your key "transponder chip" or the ignition switch may have a short. Although, it is know that the switch may be stuck on the OFF position.Why wont my 1990 cadillac deville start from the solenoid switch or with the key?Sounds like the ignition switch is bad