PHP File_put_contents not working-Collection of common programming errors

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@file_get_contents is working fine and the header location change to the downloaded file also works, but either the hit_count increase or @file_put_contents isn’t working, because the number with the file doesnt increase by 1. I’ve set the file permission to 777, but when I try to set the directory permission to 777 also I get a 500 internal server error saying “The server encountered an unexpected condition which prevented it from fulfilling the request.”