Remember the problems Samsung Focus caused when you try to use a new card in its non-hot-swappable slot? Well, the things have finally started to make sense. The cards cannot be read on any other device not because they are dead, but because they are secured on a deep system level.
When you configure a card to work with Windows Phone 7 device the OS generates a secure password and stores it within the Flash memory. Then your card is being formatted and becomes password-secured. It can work only with device that has the right password stored.
Although the SD is meant to be used that way, today there are no mainstream digital devices that make use of the feature. Because of this, there are very few platforms that can recognize a secured card and format it. As it turned out, Symbian^3 is one of them.
Once formatted under WP7, the card becomes inaccessible for other devices. But Symbian^3 smartphones can recognize and format it. You will lose the information, but you will bring the card back to life.
You can get your card back to working order but you still do not know what card to replace it with. As I told you before, the key factor is the random access speed. It turns out that quite unexpectedly high speed class microSD cards usually have higher RAS as a performance compromise. Of course this does not mean you go to the store and buy the cheapest class 2 card as they are not guaranteed to have good Random Access Speed either.
