Originally Posted by AlG
Have you tried sticking the key in the door lock on the driver's side and turning? That should open it. I've had this happen to me as well, without changing the battery in the car. Once I got in, I put the key in the ignition, started the car and the fob must have relinked with the bcm and I never had the problem again. Matter of fact, it affected both of my fobs.
I was a bit in a hurry this morning. I did try to see if the ignition key fit the door and it was not going in very easily and did not want to force it. When I get home from work I will try again.