If you see the Parking Brake Unavailable message on your car's dash, it means that there is a problem with the electronic parking brake system. This is a safety feature that prevents the car from being driven without the parking brake engaged. There are several reasons why this message may appear:
1. The parking brake may not be fully released. Make sure that the lever is all the way up before trying to drive off.
2. There may be something blocking the sensor that detects whether or not the parking brake is engaged. This could be dirt, snow, or ice build-up around the sensors. Clean off any debris and try driving again.
3. The electronic parking brake system may need to be reset. Consult your car's owner's manual for instructions on how to do this.