I stop WUAUSERV to delete the contents in my "Software Distributions" folder. I do that when I am having problems when downloading and installing Apps from the Windows Store.
The Proper way to do it is as follows:
Command prompt
net stop wuauserv
net stop bits
Go to C:\Windows\SoftwareDistribution
Delete all the contents
Return to "Command Prompt"
net start wuauserv
net start bits
That should fix your problem.