Fix Windows 8 Start screen Metro apps not working

After upgrading from Windows 7 to Windows 8 I found that the Start screen apps would not work. When they were clicked the screen cleared to the solid colour with the app icon in the middle, but then went straight back to the desktop. No Start screen Metro apps would work and they started and immediately quit. The live tiles weren't live either.

I tried a few different things, but the last one and the one that appeared to fix the problems, was turning off the security software. I was using the latest version of Avast! and right clicked the icon at the right side of the taskbar and selected the option to turn it off for 10 minutes. After switching to the Start screen the apps were all working.

I uninstalled Avast! and Metro apps work fine now. Afterwards I discovered that Windows Defender was turned on. This is basically the Windows 8 version of Microsoft Security Essentials. I wonder whether just turning off Widows Defender would have worked. I prefer Avast! so I might reinstall it some time.

If Windows 8 Start screen Metro apps are not working for you, right click the bottom left corner of the desktop and select Control Panel. Open Windows Defender, select Settings and turn it off. If Metro apps still aren't working, turn Windows Defender back on and uninstall your anti virus/spyware software. Windows Defender is a reasonably good anti virus/spyware program, so you are still protected.