Conan,
Sorry to diagree, but from personal experience, I have not, to date, (says he tempting fate) had an issue formatting a card under windows. (This with a Canon digital camera)
The secret is to ensure that it is formatted as FAT, not FAT32 or NTFS.
However, since you can delete the pictures from your cards (and any folders if using a PC) why would you ever need to format a card in the first place? It is not the same as a floppy/hard disk where errors, such as bad sectors, can appear on the disk. Generally, solid state memory is exactly that, solid state, so to speak. Re-formatting the card should make no material difference to the usability or performance of the card.
If it aint broke, don't fix it
Regards,
Shuttlebus
P.S. Three posts tonight now....
