It sounds like the issue might be with the display on your AIO (All-In-One) PC rather than with the operating system. Since you were able to connect your PC to your smart TV using HDMI and it worked fine, it suggests that the computer itself is functioning correctly.
Here are some troubleshooting steps you can try to determine if the issue is with the AIO PC's screen:
1. Check the connections: Make sure all cables connecting the AIO PC to the display are secure. Sometimes a loose connection can cause display issues.
2. Restart the AIO PC: Sometimes a simple restart can resolve display issues. Try restarting your AIO PC and see if the display comes back.
3. Update graphics drivers: Outdated or corrupted graphics drivers can cause display problems. Try updating your graphics drivers to the latest version to see if that resolves the issue.
4. Check display settings: It's possible that the display settings on your AIO PC have been changed, causing the screen to not display properly. Check the display settings in the operating system to ensure they are configured correctly.
5. Run hardware diagnostics: Some AIO PCs come with built-in hardware diagnostics tools that can help identify hardware issues. Check if your AIO PC has any diagnostic tools and run them to see if they detect any problems with the display.
If after trying these steps the issue still persists, it's likely that there is a hardware problem with the AIO PC's screen. In that case, you may need to contact the manufacturer for further assistance or consider taking it to a technician for repair.