Posting this here because this was driving me crazy. I bought my desire over eBay. It came without an sd card, no problem I popped in my 8gb Kingston card. I happily used Doggcatcher for months without issue. Then, every once in a while I started getting card corruption, card is read-only. It seemed to be connected to Doggcatcher, but really the app was just the messenger of the bad news. I replaced the card with an 8GB Patriot card. Card corruption was worse. Card would corrupt almost instantly on any sd card access. Called HTC. They couldn't help me, but told me the phone is shipped with a Sandisk card. Picked up an 8GB Sandisk from Wallymart and it works perfectly!!!