It appears be an issue with the windows registry. Something changed the registry that is not detecting the external monitor.
You could try to uninstall any Intel(R) graphics driver from Control Panel and reinstall the latest version.
Also, you may try running system restore:
To restore your PC to an earlier point in time:
1. Swipe in from the right edge of the screen, and then tap Search.
2. Enter Control Panel in the search box, and tap or click Control Panel.
3. Enter Recovery in the Control Panel search box, and then tap or click Recovery.
4. Tap or click Open System Restore, and then follow the instructions.