Samsung SCH-A990
Problem with microSD???
I had a hard time installing my card. I pushed it in as far as possible with my finger, but it would not "latch". If I closed the little door and pressed on it, the phone would recognize, otherwise it would not. I ended up having to use a small screwdriver to both fully engage the card and to pop it out. So first, I would make sure the card is fully engaged. Second, and you probably already did this, but try to format the card with the phone (options menu under card memory).