This 0x80240030 error means "WU E INVALID PROXY SERVER". That is, there is some trouble to proxy list.
Suggestion one:
Start > Control Panel > Network and Internet Connections > Internet Options > Connections > LAN Settings... If the box "Use a proxy server for your LAN" is checked, click on Advanced. and remove everything in "Exceptions" section. Now, Start > Run and type cmd. On the command line screen write this lines and hit ENTER after each one:
proxycfg -d net stop wuauserv net start wuauserv
Go to Windows Update again.
Suggestion two:
Go to firewall or proxy settings and add these sites to the exceptions:
