After installing update laptop will not connect to monitor. Monitor says no input device detected

[jacquit]

I think I made a major mistake when I downloaded windows 11 on my laptop. Since then I've had no sound and need to use headphones with a mic. Today I installed windows updates and now my laptop will not connect to my monitor. It worked this morning but after the update the monitor doesn't detect an input device. My surface works with the HDMI so it's the laptop and the only difference was the update. Help. I'm demented with this.

[Max3Aj]

@jacquit, Welcome to HP Support Community. 

Thank you for posting your query, I will be glad to help you. 
I understand how frustrating it can be when your external monitor stops working after a Windows update, especially when everything was working fine earlier in the day.

Let’s walk through some steps to help resolve the issue with your HP Pavilion x360 Convertible Laptop PC 14-dh0525sa not connecting to your monitor after the Windows 11 update.

Step-by-Step Troubleshooting

Check Display Output Settings

Sometimes updates reset display configurations.

• Press Windows + P and select Duplicate or Extend.
• If nothing shows, try Project only on Second screen to force output to the monitor.

Reconnect and Restart

• Disconnect the HDMI cable from both the laptop and monitor.
• Power off both devices.
• Reconnect the HDMI cable securely.
• Power on the monitor first, then the laptop.

Update or Roll Back Display Drivers

Windows updates can sometimes install incompatible drivers.

• Right-click Start > Device Manager.
• Expand Display adapters.
• Right-click your graphics driver (Intel UHD or similar) > Properties.
• Go to the Driver tab:
  • If Roll Back Driver is available, click it.
  • If not, click Update Driver > Search automatically.

Alternatively, download the latest drivers directly from HP: Official HP® Support

Check Sound Settings (Post-Windows 11 Upgrade)

If you're also experiencing sound issues:

• Right-click the sound icon in the taskbar > Sound settings.
• Under Output, ensure the correct device is selected (e.g., “Speakers - Realtek”).
• If only headphones work, reinstall the audio driver from the HP link above.

Run HP Support Assistant

HP Support Assistant can automatically detect and fix many issues.

• Download or open it from here: HP Support Assistant | HP® Support
• Run a full system check, especially for Display and Audio.

Additional Tips

• Try a different HDMI cable or port (if available).
• Test the monitor with another device (you mentioned your Surface works- great!).
• If the issue persists, consider uninstalling the latest Windows update:
  • Go to Settings > Windows Update > Update History > Uninstall updates.

I hope this helps. 

Take care and have a good day. 

Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. Select "Yes" on the bottom left to say “Thanks” for helping! 

Max3Aj

HP Support