The "naming error" has occurred because the card has been filled to capacity and the specific numbering system that the camera uses has a limited range. If you have not already transferred all of the photos from the card to the computer and you wish to try to recover them, please follow the procedures in the next section. If you do not need the photos that are on the memory card, please skip down to "RESTORING THE MEMORY CARD".
You can possibly recover them by using photo recovery software. (Your odds are better if you have not continued shooting with the card) . Connect the memory card so that it can be accessed like a removable hard drive on your computer.
For windows Try the Program Download at the link below. (This one will allow you to recover up to 1gb of photo files absolutely free and save them to a new folder on your hard drive.)
Make sure that before you open the program, after installing it, put the card in first. When you open the program, it will try to detect it when you click on "Media Recovery".
If unsuccessful try (The ones below have a charge to save the recovered files)
http://www.tech-pro.net/flash-recovery.html or http://www.cardrecovery.com/
For Mac Try
http://www.stellarinfo.com/mac-photo-recovery.htm or https://www.piriform.com/recuva
If the program is able to recover the photo files you will be given the option to purchase (usually around $40) the function that allows you to save and retain your photo files. Depending on how important these photos are, can determine if the cost is worth it.
RESTORING THE MEMORY CARD
In either case, the card should be able to be made usable again.
With the card in the camera:
Go to the Setup Menu
Scroll down to "File Numbering"
In the Menu then,
Select Yes or OK
Allow the process to complete
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