Sorry things got worse. Formatting does erase your files from the memory, but it also frequently fixes the microSD problem.
It shouldn’t change good copies to bad ones.
Were your files mp3s or were they from a subscription service? Do you still have other copies somewhere?
As long as there’s nothing on there, you could format it again and try again. The other thing you can do is a firmware update, from this thread. Don’t use the updater–there are no more updates. Download the “All Regions” link for your version.
With the microSD problem, there are other possibilities. The card could be going bad–you’d have to check it in another device. The slot in the Fuze could be dying, too, which is not something that can be repaired.
