CRNA and Expo not working

Expo Development Tools
1

Hi all,

I am struggling for 2 days now to get an sample Native-App working together with the Android Expo app. I read a lot of errors regarding network adapter configuration and stuff like that but I am not able to understand the error.

I created an app like shown on the get-started page and installed the Expo app on my Android device.

After entering npm start the server starts and as soon as I hit the q-button the QR-Code is shown:

C:\Users\Markus\Desktop\wimp>npm start

> wimp@0.1.0 start C:\Users\Markus\Desktop\wimp
> react-native-scripts start

13:23:20: Starting packager...

[QR-CODE]

Your app is now running at URL: exp://192.168.178.34:80

View your app with live reloading:

  Android device:
    -> Point the Expo app to the QR code above.
       (You'll find the QR scanner on the Projects tab of the app.)
  iOS device:
    -> Press s to email/text the app URL to your phone.
  Emulator:
    -> Press a to start an Android emulator.

Your phone will need to be on the same local network as this computer.
For links to install the Expo app, please visit https://expo.io.

Logs from serving your app will appear here. Press Ctrl+C at any time to stop.

 › Press a to open Android device or emulator.
 › Press s to send the app URL to your phone number or email address
 › Press q to display QR code.
 › Press r to restart packager, or R to restart packager and clear cache.
 › Press d to toggle development mode. (current mode: development)

If I scan the QR the expo app tells me that I cannot connect because of an socket-timeout. Both, my windows machine where the server is running and my mobile device are both in the same WLAN.
Sniffing the network traffic using Wireshark I see that my mobile device sends SYN packets to the server but I never reacts with an ACK.

Any ideas what is going wrong?

2

Are you able to ping between a phone and a computer?

Also: I noticed you’re working on Windows and mentioned wireless connection - make sure that firewall is not blocking outcoming connections

3

Mmh. I can ping my mobile but from my mobile I cannot ping my windows machine. Just seeing ICMP-Echo Requests but not even one response.
Because it is all in my private network I expect that the windows firewall will accept everything or am I wrong?

4

You were totally right. Because my WLAN adapter was configured as “public” network profile it blocked all incoming connections with no exceptional rule.
I changed my adapter to use the “private” network setting and it worked fine for me. Thanks for pointing me into the right direction

5

Great, that’s exactly what I was thinking about. Happy to hear that you solved it!

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