Unexpected EOF Stream.Read

I am reading data from a Stream & writing it to a file.  I successfully transferred 700+ files this way.  However on one of the files, I received the error "Received an unexpected EOF or 0 bytes from the transport stream. ".  The file seems ok & it seems to have transferred the full file before receiving this error.  What does this error mean? 
 
C# code used to transfer
byte[] buffer = new byte[1024];
int bytesRead = responseStream.Read(buffer, 0, 1024);
    while (bytesRead > 0)
    {
        localfileStream.Write(buffer, 0, bytesRead);
        bytesRead = responseStream.Read(buffer, 0, 1024);
    }
 
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