# device.load() throw TypeError
**URL:** https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210
**Category:** mediasoup libraries
**Created:** [June 6, 2020, 1:05pm UTC](https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210 "2020-06-06T13:05:27Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@nodejscss](https://mediasoup.discourse.group/u/nodejscss)
#### Post date: [June 6, 2020, 1:05pm UTC](https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210/1 "2020-06-06T13:05:27Z")
Hi, ibc,
I get the TypeError when I excute device.load(routerRtpCapabilities), that issued on github, [https://github.com/versatica/mediasoup-client/issues/120](https://github.com/versatica/mediasoup-client/issues/120) .
Please help me to fix the issue.
Thank you so much.
//-------------------------------------------------------
on server side:
const worker = await mediasoup.createWorker(
{
logLevel : config.mediasoup.workerSettings.logLevel,
logTags : config.mediasoup.workerSettings.logTags,
rtcMinPort : Number(config.mediasoup.workerSettings.rtcMinPort),
rtcMaxPort : Number(config.mediasoup.workerSettings.rtcMaxPort)
});
const { mediaCodecs } = config.mediasoup.routerOptions;
const rtpCapabilities = mediasoup.getSupportedRtpCapabilities();
console.log(rtpCapabilities);
// Create a mediasoup Router.
const mediasoupRouter = await worker.createRouter({ mediaCodecs });
console.log(mediasoupRouter.rtpCapabilities);
signaling.emit(mediasoupRouter.rtpCapabilities);
//----------------------------------------------------
on client side:
import { Device } from ‘mediasoup-client’;
import mySignaling from ‘./my-signaling’; // Our own signaling stuff.
try {
// Create a device (use browser auto-detection).
const device = new Device();
// Communicate with our server app to retrieve router RTP capabilities.
const routerRtpCapabilities = await mySignaling.request(‘getRouterCapabilities’);
console.log(routerRtpCapabilities); // see the following log
// Load the device with the router RTP capabilities.
await device.load({ routerRtpCapabilities }); // throw TypeError
}
catch (e) {
console.log(e);
}
---
### Author:  [@nodejscss](https://mediasoup.discourse.group/u/nodejscss)
#### Post date: [June 7, 2020, 4:26am UTC](https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210/2 "2020-06-07T04:26:15Z")
Hey,
I find the reason and resolve it, that is my signaling problem.
Thank you.
---
### Author:  [@matrixhacker0001](https://mediasoup.discourse.group/u/matrixhacker0001)
#### Post date: [July 25, 2020, 5:50pm UTC](https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210/3 "2020-07-25T17:50:51Z")
Hey, i just want to know.
What is your signalling error in this…??
I m also stucked in this but not able to find any docs related to it.
---
### Author:  [@ethand91](https://mediasoup.discourse.group/u/ethand91)
#### Post date: [July 27, 2020, 2:00am UTC](https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210/4 "2020-07-27T02:00:46Z")
How are you passing routerRtpCapabilities to the device?
Please make sure it’s a JSON object.
---
### Author:  [@lzxysf](https://mediasoup.discourse.group/u/lzxysf)
#### Post date: [August 5, 2020, 9:30am UTC](https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210/6 "2020-08-05T09:30:28Z")
why must json?i change it to json but not work too.
---
### Author:  [@lzxysf](https://mediasoup.discourse.group/u/lzxysf)
#### Post date: [August 5, 2020, 11:22am UTC](https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210/7 "2020-08-05T11:22:24Z")
Have you know that?I am also stucked in that.
---
### Author:  [@matrixhacker0001](https://mediasoup.discourse.group/u/matrixhacker0001)
#### Post date: [August 5, 2020, 11:35am UTC](https://mediasoup.discourse.group/t/device-load-throw-typeerror/1210/8 "2020-08-05T11:35:14Z")
I just got the error in my [socket.io](http://socket.io) protocol and just solved it… thnx btw