Key Not Recognized

Hi All, I am new to the forum as I just joined, so I hope I am posting properly. I am in a real jam, battery died on my banana key fob, so I changed it. I also changed the battery on my spare fob as well. Here is the problem scenario:

I went to unlock the car, car would not unlock so I unlocked it manually. Went to start the car and got key not recognized message. I tried the spare key, same message. So I assumed that I should change both batteries which I did. I had to leave for work so took the other car and went to auto store to get the batteries and installed both....mission accomplished,,,I thought. Got home went to start the car, same message with both keys....key not recognized. Also could not open trunk.

So I had it towed to the local shop, small town in Maine (US) as closest Saab mechanic miles away. These folks were good enough to call a Saab place for some advice and they were advised that it had to be something other than the keys...well that did not work as starter was checked and a relay replaced. So I am in the hinterland here and need some help. I did review threads and tried a few suggested solutions such as disconnect negative battery terminal to reset electronics and turn ignition to on, hold down the fob open lock switch until the little window appeared and tried to start car....no luck. Suggestion is new key at $1,300!!!!..That is what I paid for the car!!! Help!!! I need this car and hope that someone can offer me a solution.

Thanking all in advance for their help - Doug