# ReferenceError: Can't find variable: RTCRtpReceiver

**URL:** <https://mediasoup.discourse.group/t/referenceerror-cant-find-variable-rtcrtpreceiver/3199>\
**Category:** mediasoup libraries\
**Created:** [August 19, 2021, 4:25pm UTC](https://mediasoup.discourse.group/t/referenceerror-cant-find-variable-rtcrtpreceiver/3199 "2021-08-19T16:25:05Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![habilpekdemir](https://avatars.discourse-cdn.com/v4/letter/h/a9a28c/32.png) [@habilpekdemir](https://mediasoup.discourse.group/u/habilpekdemir)\
**Post date:** [August 19, 2021, 4:25pm UTC](https://mediasoup.discourse.group/t/referenceerror-cant-find-variable-rtcrtpreceiver/3199/1 "2021-08-19T16:25:05Z")

</div>

hi,  
I try to build a mobile app with react-native , on server side everything works perfectly i can create router and send routerRtpCapabilities but on mobile side when i try to create device i receive this error i already google it but there is nothing i can found , i ask here maybe someone can say what is it

before advices what i done =\>

#### mediasoupClient.detectDevice()

Performs current browser/device detection and returns the corresponding mediasoup-client WebRTC handler name (or nothing if the browser/device is not supported).

> `@async`
> 
> `@returns` [BuiltinHandlerName](https://mediasoup.org/documentation/v3/mediasoup-client/api/#BuiltinHandlerName) | undefined

```auto
const handlerName = mediasoupClient.detectDevice();

if (handlerName) {
  console.log("detected handler: %s", handlerName);
} else {
  console.warn("no suitable handler found for current browser/device");
}

```

when i run code above to check browser result === // no suitable handler found for current browser/device

so what am i gonna do reinstall Chrome or Edge11 ?

and also  
react-native-webrtc globalRegistiry is done with all build.gradle and java etc

reasen can be Browsers ===\>\>

if i use // const device = new Device({handlerName: “Edge11”})  
i can create device but can not load it gives this error  
error log is // ReferenceError:Can’t find variable: RTCRtpReceiver

and if i use // const device = new Device({handlerName: “Chrome55”})  
i ca not even create device and error log  
// ReferenceError: Can’t find variable: MediaStream

## here is the code =\>

import \* as mediasoup from ‘mediasoup-client’

let device = null

export async function main() {

```
try {
  device = new mediasoup.Device({handlerName: "Chrome55"})
  console.log(device.handlerName)
  
  return device
} catch (e) {
  if (e.name === 'UnsupportedError') {
    console.error('browser not supported')
    return;
  } else {
    console.error('new Device',e);
  }
}

```

}

export async function joinRoom(routerRtpCapabilities) {

```
console.log('join room')

await device.load({routerRtpCapabilities});

return routerRtpCapabilities;

```

* * *

## and react-native logs

[socket.io](http://socket.io) message: {“id”: “FaRP230022-46l2GAABR”, “type”: “welcome”}  
LOG connected to server. clientId=FaRP230022-46l2GAABR  
LOG getRouterRtpCapabilities: {“codecs”: [{“channels”: 2, “clockRate”: 48000, “kind”: “audio”, “mimeType”: “audio/opus”, “parameters”: [Object], “preferredPayloadType”: 100, “rtcpFeedback”: [Array]}], “headerExtensions”: [{“direction”: “sendrecv”, “kind”: “audio”, “preferredEncrypt”: false, “preferredId”: 1, “uri”: “urn:ietf:params:rtp-hdrext:sdes:mid”}, {“direction”: “sendrecv”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 1, “uri”: “urn:ietf:params:rtp-hdrext:sdes:mid”}, {“direction”: “recvonly”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 2, “uri”: “urn:ietf:params:rtp-hdrext:sdes:rtp-stream-id”}, {“direction”: “recvonly”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 3, “uri”: “urn:ietf:params:rtp-hdrext:sdes:repaired-rtp-stream-id”}, {“direction”: “sendrecv”, “kind”: “audio”, “preferredEncrypt”: false, “preferredId”: 4, “uri”: “[docs/native-code/rtp-hdrext/abs-send-time - src - Git at Google](http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time)”}, {“direction”: “sendrecv”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 4, “uri”: “[docs/native-code/rtp-hdrext/abs-send-time - src - Git at Google](http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time)”}, {“direction”: “recvonly”, “kind”: “audio”, “preferredEncrypt”: false, “preferredId”: 5, “uri”: “[http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01](http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01)”}, {“direction”: “sendrecv”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 5, “uri”: “[http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01](http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01)”}, {“direction”: “sendrecv”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 6, “uri”: “[draft-ietf-avtext-framemarking-07](http://tools.ietf.org/html/draft-ietf-avtext-framemarking-07)”}, {“direction”: “sendrecv”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 7, “uri”: “urn:ietf:params:rtp-hdrext:framemarking”}, {“direction”: “sendrecv”, “kind”: “audio”, “preferredEncrypt”: false, “preferredId”: 10, “uri”: “urn:ietf:params:rtp-hdrext:ssrc-audio-level”}, {“direction”: “sendrecv”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 11, “uri”: “urn:3gpp:video-orientation”}, {“direction”: “sendrecv”, “kind”: “video”, “preferredEncrypt”: false, “preferredId”: 12, “uri”: “urn:ietf:params:rtp-hdrext:toffset”}]}  
ERROR new Device [ReferenceError: Can’t find variable: MediaStream]  
LOG join room  
WARN Possible Unhandled Promise Rejection (id: 0):  
TypeError: null is not an object (evaluating 'device.load()

If anyone need some other logs or want to test other things just ask me  
Thanks