What file extension does one need to use to upload a photo on this site please?
The uploading problem was probably not a filetype issue - but a matter of your profile not having full privileges. I have move you out of the "unassigned" user category to the "chocolate maker" category so you should now be able to upload.
GIF, JPG, and PNG are all supported.
clay - http://www.thechocolatelife.com/clay/