Error 800F0826

Windows Update error 800f0826 is displayed when an update for Windows has failed to install and is preventing you from installing additional updates. Error 800f0826 does not identify the update that has caused the problem. The update that has caused the problem will display a different error. This problem affects updates for Windows only and does not prevent you from installing or automatically receiving updates for otherMicrosoft programs, such as the Microsoft Office System.

See - http://windows.microsoft.com/en-US/windows-vista/Windows-Update-error-800f0826

You'll need to find the update that is failing and what error code it is displaying.

1. Open Windows Update by clicking the Start button , clicking All Programs, and then clicking Windows Update.
2. In the left pane, click View update history.
3. Find an update for Windows that has failed to install, and then double-click the update to view more information.
   Updates that have failed to install will display Failed under Status, next to the update name.
4. In the Windows Update dialog box, next to Error details, review the error code for the failed update.

Either follow the links in the Windows Update dialog box under More Information or Help and Support to try to fix the problem, and then try installing updates again by using Windows Update in Control Panel or post back with the error code so perhaps someone may be able to assist further.

Troubleshoot problems with installing updates
http://windows.microsoft.com/en-US/windows7/Troubleshoot-problems-with-installing-updates

Open the Windows Update troubleshooter
http://windows.microsoft.com/en-US/windows7/Open-the-Windows-Update-troubleshooter