I tried snoopy's suggestion, got some errors. Is there a package for the taskbar itself?

Add-AppxPackage : Deployment failed with HRESULT: 0x80073CF6, Package could not be registered.
error...

I've had this problem for a while now. The buttons on my taskbar don't work. launching programs works fine, but opening the start menu, volume controller, wifi controller, search do nothing. no...