Maybe your WU is not enabled.
Open control panel, tick administrative tools, then click on services and look for windows updates if it's enabled.
If it's not , enable it and see if that solve your problem.
My Computer
At a glance
win7 home premium-64bit-SP1-IE10T6600 2.2Ghz4 GbATI Mobility Radeon HD 4530
I think I've found a solution I re-installed windows using recovery solution and then I upgraded windows before installing any updates on the current version of windows. after upgrading I started downloading updates and now my windows is up to date with no errors.