Memory stick read only?

[OzzieGT]

So we just bought a 1gb memstick replacement for our camera. That's working fine. The problem is I tried popping the old 256mb sandisk memstick pro into the camera and the camera says it is locked? I tried it in my car reader and Windows is saying the stick is write protected as well. The lock switch is set to unlocked. Any ideas what has happened to my poor memstick?

 

[OzzieGT]

Nobody?