hi i need a code for file transfer

i wrote the code like this

Server.connection.si_filetransfer.send(
/* jshint +W106 */
data.to,
sid,
data.filename,
data.file.size,
data.file.type,
function(err) {
if (err) {
return console.log(err) //the error is coming here
}
Server.connection.ibb.open(cn(data.to), sid, Cryptocat.otr.chunkSize, function(err) {
if (err) {
return console.log(err)
}


the error is coming like that

"Error: [object Element]
at Object.Strophe.addConnectionPlugin._fail (http://127.0.0.1:58889/http-services...sfer.js:107:10)
at Object.eval [as handler] (http://127.0.0.1:58889/http-services...min.js:2:19333)
at Object.f.Handler.run (http://127.0.0.1:58889/http-services...min.js:2:15804)
at eval (http://127.0.0.1:58889/http-services...min.js:2:22417)
at Object.f.forEachChild (http://127.0.0.1:58889/http-services....min.js:2:8457)
at Object.f.Connection._dataRecv (http://127.0.0.1:58889/http-services...min.js:2:22250)
at Object.Strophe.Bosh._onRequestStateChange (http://127.0.0.1:58889/http-services/emulator-webserver/ripple/userapp//C/Users/Administrator/AppData/Local/XDK/xdk-scratchdir/2b05c0c1-bf27-465a-9ddb-da90dcdb5336/platforms/ios/www/Js/strophe.min.js:3:6555)"

can any one tell tell me waht is the problem in my code

i am using local server only