Windows Error Code 80070490

Hi everyone. I was trying to install Windows 7 Service Pack 1 (KB976932) on Windows Update and I got error code 80070490. How do I solve it? Thanks



Excellent Member
Microsoft Community Contributor
If the Readiness Tool doesn't fix the situation, are you running any type of anti-virus or firewall beside a Microsoft product?

This is one Microsoft site to check, which suggests some things mentioned already. But there may also be a problem with a prior update not being yet installed. How long have you been trying?

@Elmer, yes I just ran it. It installed Hotfix for Windows (KB947821) and then I used the troubleshooter for Windows update from the site Saltgrass suggested. Then I restarted the computer and it still didn't work. I still got error code 80070490: Windows Update encountered an unknown error. Any more advice?



Excellent Member
Microsoft Community Contributor
The error mentioned seems to refer to an access denied situation.

I suppose we need to look at your WindowsUpdate.log in the Windows folder. If you right click it and select send to, compressed (zip) folder, it will allow you to make a .zip file you could attach using the Paperclip.

If you don't want to do that, copy the last 3 or 4 days of events and paste into notepad. Then zip and attach.

If you want to see if you can find a definition for the error number, you can open two different logs and search for the number. It should have a definition next to the number in one of the logs, probably CBS.log.

WindowsUpdate.log and CBS.log in the Windows\Logs\CBS folder. You may have to copy them to the desktop to open but use the find function in Notepad to search.

Edit: I should also ask if the CheckSur.log showed any errors? I also found a better definition at this Microsoft site and the error seems to mean:
Windows could not search for new updates.
Which probably means a prior update has not been installed correctly.

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Here's the Windows Update log. I just tried running it. Let me know what to do next please.




Excellent Member
Microsoft Community Contributor
Your system is stuck for some reason on one of the 4 parts of the SP1 update. Out of the 4, it is the only one that keeps saying it is Queueing the download rather than "already downloaded".

The location it is trying to retrieve the file from is:


Not sure exactly what the system will allow you to delete, but I would start by trying to delete that location (18e...) and see what happens. Maybe it will resync itself.

If that does not help, delete or rename the Download folder. Again give it time to correct, and it might take enough time to re-download the files.

If that doesn't help, then rename the SoftwareDistribution folder. It will also take quite a while (maybe days) for the system to reset.

There is information kept in the Registry that seems to keep track of the updates and what packages are available and ready, but I do not know any changes that could or should be made there.

The error means that access to the file is denied or it is missing. Since this is the only file with that error, I will have to believe it is missing or corrupted.

If you want to check the WindowsUpdate.log yourself, use notepad and search from the bottom up for the word FATAL which should have other text like the quote below.

Starting install of CBS update 9B3E0557-1739-409A-AFE2-CE51B1CC706F
Handler CBS package identity: Package_for_KB976932~31bf3856ad364e35~x86~~

Handler Installing express with source=C:\windows\SoftwareDistribution\Download\18e2c83e42cc8f0cc17b5dbfaf982690, workingdir=C:\windows\SoftwareDistribution\Download\18e2c83e42cc8f0cc17b5dbfaf982690

Handler FATAL: CBS called Error with 0x80070490,
Edit: The CBS mentioned sends messages to a CBS.log in the Windows\Logs\CBS folder. You would also have to copy it to the desktop and open with notepad. Do a search for the error number.

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