An internal error occurred while installing the service pack. Error code: 0x80070490

This post will cover how to fix the Windows Vista SP1 error: An internal error occurred while installing the service pack. Error code: 0x80070490

While sometimes this error can be seen because of bad ram or a hard drive that has some corrupt files, it typically means that there is some issues with the windows folder permission from a previous patch. It can also be caused by security suites like Norton 360 preventing Windows patches from executing propperly!

The trick is to rename the following folder:

C:\Windows\System32\LogFiles\WMI\RtBackup
 
The problem, however, is that because the permissions on this folder are wrong, you can’t rename it yourself without some additional help. You’ll need to download the Unlocker utility:
http://ccollomb.free.fr/unlocker/

Downloaded and installed unlocker
Right click on it, select properties > Compatibility tab > tick “Run as Administrator” and click OK.
Now, run Unlocker.
Go to the Windows Start menu. In the run box at the bottom of the menu, type in: C:\Windows\System32\LogFiles\WMI\ and press Enter.
Windows will now open the folder that contains the dodgy RtBackup folder. Right click on RtBackup, and select “unlocker”.
You will get a message reading:
“No locking handle found. However Unlocker can help you deal with this object. Choose the action you want to perform on this object.”
Select “rename” from the dropdown menu in Unlocker, and type a name for it (e.g. RtBackup.bak).
Click Ok.
You will now get an error message from Unlocker saying, “The object could not be renamed. Do you want to perform the requested rename operation at next reboot?” Click “Yes”.
Reboot Vista.
Unlocker will now rename the RtBackup folder as Windows starts up, and Windows will recreate the original RtBackup folder with correct permissions, which allows the Event Logger service to work

 
Now Vista SP1 might work but I am assuming you will still get the “An internal error occurred while installing the service pack. Error code: 0x80070490” error.
You will need to download the “Windows Readiness Tool” You can find it here:
http://support.microsoft.com/kb/947366
Download and install the version that you need. ie. 32bit or 64bit.
Once that installs (it will most likely take quite a while), Use Windows Update to keep installing the updates. Eventually you will get to Windows SP1. You should now find that it now installs just fine. You should no longer get the error:  An internal error occurred while installing the service pack. Error code: 0x80070490
Finish the rest of the updates.