Key not accepted error in 2000 saab 9-5

i got a key not accepted message on the console and the car wont start i tried both keys but i keep getting the message anybody know why this is or how to fix it??

This similar problem happened in my girlfriend's 2000 Beetle. I tinkered in it for about 20 min waiting for her towtruck. I unplugged the battery to see if it would reset and all it did was reset the radio, I still got the same message. So I type in the radio code and I noticed the message dissapeared. I tried it out of sheer luck and it worked! I don't know if this will work for you but its an easy try.

the whole radio code thing bothers me..its a fund raiser for the stealerships...

I was told by (2) mechanics that there is a sensor mounted on top of the ignition switch that looks at the magnetic "chip" in your car key when you stick the key in. If it doesn't think you have the right key (because of a defective key or "chip") it won't let the ignition switch start the car.

Good chance that the TWICE module is toast.  See the dealer about it. The only way to tell is to hook it up to a tech2.

roto right if the twice is fried it will cost over 300 to repair
 

My 95 is a '99 and I've had the problem for over a year.  The dealer quoted me $1,100 to fix.  So I didn't.  Anyway, there is a workaround.  Insert key into ignition and turn the key as if to start.  Nothing will happen.  Release the key but do not remove it.  Push one of the three buttons (doesn't matter which) on your alarm. Now turn key to off position and then turn key to start.  It should start at that point.  You'll still have a message on your display "key not accepted."  Although this works fine, you'll find you can never valet park again!  When someone asks why I have to go through all this I just tell them it's an added security feature. :) 
Good Luck!

yeah, I just recently found out about this workaround too.