Did you try other (larger) values for the buffer size? Did you look at http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/IOUtils.html#copy%28java.io.InputStream,%20java.io.OutputStream,%20int%29 or possibly http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/IOUtils.html#copyLarge(java.io.InputStream,%20java.io.OutputStream,%20byte[])