I think I found out how to utilize the Sandisk Magicgate 256mb memory stick on Sony Digital Camera. Just did it successfully! I have a DSC-P73 Sony Cyber-shot.
First, I insert the Sandisk stick into the camera. Of course, I get C:13:01 memory error.
Then I plug my USB cable from my camera to my computer.
After that, I go to "My Computer" to find the drive that my camera is connected.
Then, I right click the drive and select format. I have Window XP home edition. I click the box where it says "quick format" and click "OK"
Finally, Whalla! There is connection! No more C:13:01 error!
Please let me know if this works for you.
Soli Deo Gloria!