Quote: It is important that the card(s) you are using are formatted in the camera. Cards formatted in other cameras, or formatted via the computer, may have problems.
This is honestly one of the biggest loads of horse hockey ever spread across the Internet. You'll even hear seasoned professionally state this is required, but it is all anecdotal FUD (Fear ,Uncertainty and Doubt). There is no concrete evidence to back up such claims. I've formatted cards across nikon, canon, DSLRs and point & shoots for years and never had a problem with regards to compatibility.
Memory cards and current cameras use a well founded standard that is not affected by brand or model of camera.
Think about it... if the standards were not followed, would your computer be able to read the card when you go to transfer your photos? No, of course not.
No one is going to stray from the standards that everyone relies upon.
Format it on your computer, or by another camera...
The ONLY issue I've seen has been with using a card with more memory than the camera could handle (such as an 4G card with a ten year old camera that only handles 1G)... in which case it may re-partition the card to the smaller size.
This is mildly difficult to fix, and formatting in-camera can not fix. Regardless, the resulting state is still not incompatible with newer cameras nor is it permanent -- just need special care to regain the partitioned areas.
One note, some brands create extra folders or leave minor cruft behind. It is not a bad idea to reformat to clean up the extra stuff and give yourself an extra photo or two... but it won't reduce corruptions issues.
Anyway, it is far more likely the card was corrupted either by freak static charge, was defective, perhaps you bought one those "ebay specials" for $.01 a ton, or perhaps it was a counterfeit branded card.
As suggested, you can try some recovery software. If you're lucky, only the file system itself got a bad tick and lost where the files were located. The images themselves may be intact.
... and stay with name branded memory cards from Reliable Sources.
BTW, "Transcend" is relatively inexpensive but has a good reputation. Been using 8G & 16G versions of their cards for a couple of years without error.
Last edited by amoringello; 12-16-2011 at 04:28 AM.