Google "recovery software". There are all kinds of free programs that will scan the card and find all the pictures on it. I found out that deleteing the pictures doesn't really erase them from the card, it only puts a different extension on the end of the jpg. It makes it look like it is gone from the card. The only way to totally get rid of them is when they are written over by new ones, or if you reformat the card.

I bet it wasn't taking any pictures after the error, but you can always give some recovery program a try and see if there are some from before the error. I use Pandora Recovery. I have heard stories from some people using these programs after buying used memory cards and finding some real interesting pictures.... if ya know what i mean.