Quite often my blank SD cards cause a warning message to pop up in my my Nikon DSLR reading' Card is damaged'ie throw away or use another. After some fiddling with the slide lock and or wiping the contacts it becomes useable again magically. Im getting tired of this as I cannot trust these expensive cards. These cards have not been subjected to rigourous use or abuse. I think the brand was Sandisk Ultra 8GB.Gold.