Hmmmmm.. green light stuck on would indicate to me that the problem happened when the camera was transfering data to the card. It could be a hand shaking glitch or an issue with the card as the data transfer never completed. I would first try using a different card. The DSLR is really a computer that takes pictures. Any data transfer that does not complete, either from handshaking or error, can only be cleared by doing an Initial clear as you did ... by removing the battery and allowing all the logic to reset. Question - did the battery have a good charge level when the problem occured? Logic does strange things when voltage drops to a certain point.