I just upgraded to Windows 10 a couple of days ago and it's been an absolute nightmare.

The start menu frequently just stops working with no clear trigger. It reacts when I mouse over it, and it changes colour when I click on it, but no start menu appears. The same problem occurs with the search bar and the notification menu, and even right clicking on open applications.

I've installed all available updates and I've run that powershell command that was recommended to fix this issue back in the preview version. Nothing has helped.

I'm seriously close to just downgrading back to Windows 7 to escape this, but I'd like to see if I can fix it first.