The Windows 8 structure is that preinstalled product key is already embedded on the BIOS itself, and that’s why we expect it to activate perfectly, but been having this activation problem. I wonder why would it be showing expired if it has been activated previously? But if you are curious to get your product key, download this helpful utility. (for 64 bit)
Anyhow, I did some research about the error message 0xc004F074, where I tried removing the product key, reinstalling it using the slmgr command lines, also did sfc /scannow, (got an error) and even installed the missing Microsoft updates. Worse comes to worst, I might reset the installation of Windows 8.
Ok so what does my issue with brightness controls (F11, F12) got anything to do with it? I pressed the F11 and F12 keys back and forth, my brightness is set to dim! I had my 5 minute panic, I wonder if the troubleshooting steps I did with the activation and windows updates caused it.
The Windows automatic update apparently installs a new Intel driver, causing the brightness keys not to work. Duh, automatic installation of updates fail! Ok recovery time, told myself. So I read from an online article about this roll back thing. So in case you experience the same brightness issue with your Lenovo Z500, here’s what you need to do:
* Go to the Properties of My Computer.
* Go to the Device Manager.
* Double Click Display adapters and highlight Intel HD graphics 4000, go to its Properties.
* Go to the Driver tab and click on Roll back driver.
The change with the rollback driver would be immediate, no need to reboot, the brightness control issue got fixed!