Windows Update Error Code 80070490
To troubleshoot this issue, I suggest we first reset permission and
reinstall Windows Update Agent 3.0.
Step 1: Reset permission
1. Please download the subinacl.msi file from the following link and save
the installation patch onto the Desktop:
http://www.microsoft.com/downloads/details.aspx?FamilyID=e8ba3e56-d8fe-4a91-93cf-ed6985e3927b&displaylang=en#AffinityDownloads
2. Please go to the Desktop and double click the downloaded file.
3. install Downloded fie to your system. To do this Run as adminstration to command promt.
4. Add installation file to windows path PATH and run notepad
5. Copy the following commands and then paste them into the opened Notepad
window:
@echo off
subinacl /subkeyreg HKEY_LOCAL_MACHINE /grant=administrators=f
subinacl /subkeyreg HKEY_CURRENT_USER /grant=administrators=f
subinacl /subkeyreg HKEY_CLASSES_ROOT /grant=administrators=f
subinacl /subdirectories %SystemDrive% /grant=administrators=f
subinacl /subkeyreg HKEY_LOCAL_MACHINE /grant=system=f
subinacl /subkeyreg HKEY_CURRENT_USER /grant=system=f
subinacl /subkeyreg HKEY_CLASSES_ROOT /grant=system=f
subinacl /subdirectories %SystemDrive% /grant=system=f
@Echo =========================
@Echo Finished.
@Echo =========================
@pause
6. After pasting the above commands, please close the Notepad window. Choose
Save when you are prompted to save the file. Type "reset.bat" as the file
name and choose Desktop from the left panel as the save location.
7. Refer to the Desktop and right click the reset.bat file, then choose "Run
as administrator."
8. You will see a DOS-like window processing.
NOTE: It may take several minutes, please be patient. When it is finished,
you will be prompted with the message: "Finished, press any key to continue".
Step 2: download Windows Update agent from http://support.microsoft.com/kb/949104 and Reinstall Windows Update Agent 3.0