Hello,
Follow the steps below and see if you can make things right.
Note:- if you have formatted the drive, simply bypass this step and go to #2 directly.
#step :1 Check whether the files are not in hidden mode.
Click on "Start" -->Run-->type cmd and click on OK.
Here I assume your removable drive as G:
Enter this command: attrib -h -r -s /s /d g:\*.* (replace the letter g with your usb or memory card or "drive" letter showed under "My Computer").
Then check if your real files will be showed.
#step :2 If your files won't show. You have to use some strong anti-virus or anti-malware programs to eliminate the virus or trojans. http://download.cnet.com/Malwarebytes-Anti-Malware/3000-8022_4-10804572.html and install it on your computer. You may also find more http://data-security-freeware.blogspot.com/2011/07/free-anti-virus-or-anti-spyware.html. Then connect your removable media. Run the software to perform a "Full Scan" of the drive which may contain those virus or trojans. '); Default selected option is "Quick Scan". This way should kill those problem makers. After that see if the file folders will be accessed normally.
#step :3 If you find your folder files missing, do not worry. Take a try of http://www.anysoftwaretools.com/file-recovery.html (take the free trial) and see if you can recover the deleted files or folders. This way should be your final solution.
your query is most welcome... ... Best regards,Abhinav