The errors can occur before SP2 or After SP2 it has been at random with some laptops\PC's.
Create a batch file called wu5_fix.bat and add the contents below.
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net.exe stop wuauserv
cd /d %windir%
rd /s softwaredistribution
REGSVR32 C:\WINDOWS\system32\wuapi.dll
REGSVR32 C:\WINDOWS\system32\wuaueng.dll
REGSVR32 C:\WINDOWS\system32\wucltui.dll
REGSVR32 C:\WINDOWS\system32\wups.dll
REGSVR32 C:\WINDOWS\system32\msxml3.dll
net.exe start wuauserv
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This is what the batch file does:
Stops the Automatic Updates Service
Removes C:\windows\SoftwareDistribution
Registers some DLL's provided for Windows Update.
then starts Automatic Updates Service.
This will fix most windows update errors.
More Soon......