W10 Missing start menu and no live tiles

[hovesteve]

I uploaded W10 yesterday morning, loved it, no problems at all. Turned on my PC this afternoon and when I click on the start button nothing happens. Also the live tiles have gone and some icons in the taskbar are missing too! Anyone got any idea? Thanks

 

[patternjake]

You have the annoying ShellUXExperienceFramework bug that prevents Cortana and start from being usable.
A major culprit is Avast, uninstall it if you have it.
Otherwise all I can suggest is switching your MS account to a local one (which fixes it but disables Cortana) or re-install Windows 10.