I taken come photos by using sony dsc-s500 model camera :: but its all shows only error file . how to recover the photos back

Are you sure you've saved all these error files on your camera memory card?
If you are 100% sure, you may have chances to get these photos back.
You can try to use a camera photo data recovery freeware that can always help restore the inaccessible photo on a camera memory card successfully for free:
http://blog4mark.blogspot.com/2012/12/photo-recovery-after-delete.html
This freeware helped a lot as the camera memory card of my friend was formatted by accident. It eventually restored all his wanted photos back completely. So, if you are also interested, you can get this freeware here:
http://www.freeware-fix.blogspot.com/2013/02/photo-recovery.html

Next time, I hope you can lean to back p everything important well.

In this case you should try some photo recovery software to rescue the lost photos from your camera, here are some programs you may rely on. Both programs can also recover videos and music.

Photo Recovery (for Windows)
Mac Photo Recovery (for Mac OS X)

Note: Before your photos are recovered, do not attempt to save more files to the camera memory card in case the original files(your photos) are overwritten. Regards