Change USB Stick

Hi,
I installed the PirateBox and all works.

Now I want to change the USB-Stick.
(Because of the size)

I formated a new USB-Stick.
Then made simply copy-paste form old to newone.
(Both sticks are 16GB.)

But It seems, that something is wrong?
Cant connect to PirateBox with the new USB-Stick?

Any ideas?
Is it possible with simply copy-paste to change the USB-stick?