hello, im not sure off what software your computer has or if yours is customed but anyway,
if you copy what ever you have on it and place it in a folder so you can keep these important files.
you can do this by right clicking on the files and then finding the copy tab.
then if you open the properties which might help tell you if its broken or locked, to do this right click on the SD card which can be found in my computer then select properties tab.
hopefully you can now view and find out what ever is wrong.
(Based on windows 7)