Anti-theft system?

The anti-theft system on my car was set off when I was trying to start my vehicle with remote starting from the key fob. The weather where we live has plunged into 20+ below zero. I haven't had any problems up until now. There's a car with a lock symbol through it on the dashboard information and the car will not start or turn over. The lights and electrical work, the fob allows me to lock and unlock the doors etc. I have tried several methods suggested online, three 10 minutes reprograming the key, putting the key in the door and holding it in the opening position for 30 seconds, none of them have worked. Does anyone have any clue how to disengage or reset it?