Today I have connected my laptop to TV. I wanted to watch a movie but I was not able to play sound on TV using HDMI. Sound settings showed me only a message "Not plugged in".
I found on the Internet that I needed to update Intel Graphics Drivers.
At first I downloaded the newest drivers but installator showed me an error: "The driver being installed is not validated for this computer. Please obtain the appropriate driver from the computer manufacter.".
I downloaded Intel® Driver Update Utility but after scanning it showed me that I can't update drivers - "A customized computer manufacter driver is installed on your computer.".
That's true. Drivers were installed automatically by Windows 10. Let's remove them and install the newest drivers from Intel.
First, download the newest drivers from https://downloadcenter.intel.com.
Then we need to uninstall current drivers but before that we should disable WiFi. Why? After we remove drivers Windows will automatically install them once again.
Go to Settings -> Network & Internet and turn off WiFI.
Go to Device Manager (Right-click on start menu icon and select Device Manager).
Find Display Adapters, right-click on Intel(R) HD Graphics and select Properties.
Go to Driver tab and click Uninstall.
Check Delete the driver software for this device and click OK.
Intel(R) HD Graphics will disappear from Device Manager.
Click on the icon below Help to Scan for hardware changes.
Device Manager will show Microsoft Basic Display Adapter.
Now we can install drivers. Run installer for Intel Graphics Drivers downloaded from https://downloadcenter.intel.com. Everything should work.
After that we can use Intel® Driver Update Utility to update all drivers.
We can turn on WiFI.
Sound via HDMI should also work ;-)
One question remains unanswered. Why doesn't Microsoft Windows install the newest version of Intel Graphics Drivers?