Key fob lost synch.
 

So I got the key fob wet. I let it dry for a couple of days and tried it.
I could lock and unlock the door with the remote , so everything is OK - right?

Well not exactly, I locked the door with the remote and then remembered I had left something in the car. So I used the key to open the door and the alarm went off.
Now the remote will not work and opening the door with the key will cause the alarm to go off.

Can I re-synch the key fob?
Any ideas on how to fix this - short of a trip to the dealer?

(and yes the alarm is terrifying to seniors and pets)

Not sure what year Boxster you have but if you have a 2001 - 2004 model year, try unlocking the car with the key in the door lock, leave the door closed to avoid triggering alarm, then press the central locking button on the key fob.