To resolve the casting error you're experiencing with EZCast after purchasing the premium feature, please follow these steps:

1. Upgrade Device Firmware: Ensure that both your EZCast device and the applications on your PC and laptop are updated to the latest firmware. This often resolves connectivity issues. Check the EZCast website or app for any available updates.

2. Verify Network Connectivity: Confirm that your PC, laptop, and EZCast device are all connected to the same Wi-Fi network. If your network router is old or has poor signal, try rebooting it or using a different network.

3. Check Device Compatibility: Make sure your devices support the required casting protocols, like Miracast or DLNA, which are essential for EZCast functionality. Additionally, verify that your operating systems are compatible with EZCast.

4. Restart Your Devices: Sometimes, a simple restart of all involved devices can fix issues. Turn off your PC, laptop, and EZCast device, then turn them back on.

5. Disable VPN: If you are using a VPN service, try disconnecting it temporarily. VPNs can interfere with the device discovery necessary for casting.

6. Check Firewall Settings: Windows Firewall or any installed antivirus software may block the EZCast application from working correctly. Review the settings to allow EZCast traffic.

7. Reset EZCast Device: If none of the above steps work, consider resetting your EZCast device to factory settings. This can often resolve stubborn issues. After resetting, set it up again to connect.

8. Contact EZCast Support: If problems persist after performing all these steps, it may be beneficial to reach out to EZCast customer support for further assistance.

By following these instructions, you should be able to resolve the casting errors on both your PC and laptop. If you'd like detailed information on troubleshooting casting issues, you can refer to the EZCast blog regarding solutions for common casting problems - learn more.