I had the same problem with a Sandisk 1GB card, even though I had reformatted it with Windows it still came up “SD error”
I read the instructions for 3.64 and on page 18 it says that it is a good idea to use a program called " sdformatter " (Google for a download) I did this, loaded the program, formatted the card using this formatter program and all is now perfect. Hope this may help you.