anti-theft 1995 grand prix

My step daughter has a 1995 grand prix, she left the battery go dead. I towed it to my house charged the battery, left the key on, but the security light still blinks. the car will not crank, but if I jump the starter it cranks great. But it will not start. Please help....

un hook the battary for about a half an hour then hook it back up that resests the computer

My step daughter has a 1995 grand prix, she left the battery go dead. I towed it to my house charged the battery, left the key on, but the security light still blinks. the car will not crank, but if I jump the starter it cranks great. But it will not start. Please help....
thanks, but that did not work, please any other idea, the dealers wants $50.00 to reset it.