Voila is making use of WebRTC and to be able to share the desktop, the sharing device as well as the network should allow UDP. Since the connection can be made but only the 'stream' is not visible, it is most likely that the UDP stream is somewhere down the line blocked (resulting in a black screen).
Please try below steps to try to solve your problem:
- Check if other people in your organization are suffering from the same issue. If the answer is yes, please check with the responsible IT department if the network implementation is executed. More (IT related) information: Network preparation: Ports, protocols and security concerns. If the answer is no, it is most probably an issue on a particular device so continue with the next steps.
- Check with the latest Google Chrome, Firefox or Microsoft Edge (Chromium based) browser if you can share your screen via https://voila.kickle.app/. If that works, continue with the next step (connection of the sender and receiver is seems to be ok). If that doesn't work either, please go back to step 1 as that is most likely related to IT implementation.
- Check if the Network profile is set to Private as Public will block certain ports and protocols. Please check again and if it is still not the solution, try the next step.
- Uninstall the Voila application from the laptop. Re-download it from https://voila.kickle.app/ and install it again. Make sure to that you allow access to your network (voila.exe is then added to the Firewall rules of the device which is essential to have wireless screen sharing working). Another option might be to install the Voila application as Administrator.