Re-register these files:
1. Click Start, click Run, type: cmd and press Enter.
2. Run the following commands pressing enter after each one:
Regsvr32 wuaueng.dll
Regsvr32 wuapi.dll
Regsvr32 wucltui.dll
Regsvr32 wups.dll
Regsvr32 wuweb.dll
Regsvr32 qmgr.dll
Regsvr32 qmgrprxy.dll
After running each command, we will receive a message stating "Succeeded".
In your registry editor go to HKEY_LOCAL_MACHINE \ SOFTWARE \ Policies \ Microsoft \ Windows \ WindowsUpdate \ AU. In the right pane, delete two values: AUOptions and NoAutoUpdate.
Now go to this location: HKEY_CURRENT_USER \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ Policies \ WindowsUpdate. In the right pane, delete this value: DisableWindowsUpdateAccess.