Multiple music +videos files

[Sachinmeet]

Hi, i have a lumia 820 with an sd card. Yesterday i transfered some videos from my pc to the phone. When i saw the videos on my phone there were 2 files of each video and deleting either one of them prevented the other from opening. Also when i saw my songs there were also many copies of same song.

Please help

 

[Sachinmeet]

And only the songs and videos i have got in the past week got copied