I've experienced a problem with windows 8.1 ever since building this pc. Basically, when using my pc, at random times the start menu stops working. I.e, when I click the start button, the menu does not come up, right click does not also work to bring up the power menu. The sidebar does not also appear. I've done a few reformats for various reasons and it's not appeared to have fixed the issue.

Pressing win+x does bring the power menu up, but the start button is still unresponsive after.

The one thing that does fix the issue is restarting explorer.exe from task manager

I'm not sure what causes this issue and was just wondering whether anyone else has experienced this, and if so, any fixes? Is it a glitch in 8.1?