Anodized (and other) themes missing

#1

I had to do a full reset on my WDTV Live SMP, and (understandably) the Anodized theme disappeared, and it reverted to Mochi.

However, when I went to change it back to Anodized, only Mochi is available.

HELP!

#2

Hi, I have never tried this, hopefully another user will be able to provide some information or guidance.