I cant access a folder from my external hard disk

[rockersunny]

i have a transcend 640G external hard disk.. The other day I was moving some movies into this hard disk and i put them in 2 folders..when i tried to open 1 of them, a window popped up asking to format disk so i cant access it....the other folder in the same drive is opening and i can access my movies there... how to retrieve that data because folder contains loads of good movies and i cant afford to lose them..... HELP ME OUT PLS!!!!!!

 

[nhasian]

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