This fix can be used on either stuck windows update downloads where you are left waiting hours at 10% or 25% through the native windows update interface OR when you try to install an update package manually and it gets stuck on “copying packages to the update cache”.
1) Perform a clean reboot first.
2) Start a cmd box as Administrator
3) Run the following commands:
net stop wuauserv
net stop cryptSvc
net stop bits
net stop msiserver
del /f /q “%ALLUSERSPROFILE%\Application Data\Microsoft\Network\Downloader\qmgr*.dat”
del /f /s /q %SystemRoot%\SoftwareDistribution\*.*
del /f /s /q %SystemRoot%\system32\catroot2\*.*
del /f /q %SystemRoot%\WindowsUpdate.log
net start wuauserv
net start cryptSvc
net start bits
net start msiserver
4) Retry automatic updates, this will clear the Windows Update cache and the automatic updates should work again through the native interface.