Unable to install updates in Windows Vista, Windows 7, Windows Server 2008 and Windows Server 2008 R2
https://support.microsoft.com/en-au/kb/2509997
Error code 0x80070490 when you use Windows Update or Microsoft Update to install updates
http://support2.microsoft.com/kb/958044
http://windows.microsoft.com/en-au/windows/windows-update-error-80070490#1TC=windows-7
If you receive Windows Update error 80070490, it means that a file (CBS Manifest) that's needed to install updates is corrupt.
The System Update Readiness Tool for Windows can correct some conditions that cause Windows Update error 80070490. To learn more about this tool, go to What is the System Update Readiness Tool? on the Windows website.
If the System Update Readiness Tool doesn't correct the problem, you'll need to repair Windows. Repairing Windows won't damage your personal files or the programs that are installed on your computer.
Once you finish the repair, you'll need to rerun Windows Update to install any updates aren't included on the installation DVD.