File Transfer download error

when i call download function it show me every time provided error

{
“code”: 3,
“source”: “http://www.seedharastah.com/bookPdf2/11shrif.pdf”,
“target”: “http://www.seedharastah.com/bookPdf2/11shrif.pdf”,
“http_status”: 200
"body": null,
“exception”: unexpected end of stream
}