I have recently had a machine re-installed with Windows 8, noticed that none of the apps were updating or installing from the Windows store.
After a while of searching the net and re trying an re trying over and over again, I found the solution below
Source : http://answers.microsoft.com/en-us/windows/forum/windows_8-windows_store/windows-8-apps-not-downloading-all-stuck-on/5e70122e-7bac-456d-a318-e8aae43fa2c3
I did this, however for me even running as administrator I couldn’t stop the service so I went into local services and stop the Windows Update (wuauserv) service, ran the next 2 commands and started the service again.
This fixed the updates but then on new app installs I received the error saying that my firewall service has to be running in order to install apps, this was easy started the Windows Firewall service and then went to the firewall settings and disabled it for domain, private and public (it’s a requirement to have the firewall disabled/off).
And now everything works great.