Windows security update error code 646

However, it is not entirely perfect, and some errors can prevent updates from being installed. One such error is Windows Update error code , which occurs when you try to install a Microsoft Office update. There are solutions to fix this error and update your system.

Windows Update errors happen to many people, so feel free to share your stories about them or tips for overcoming them in the comments. Windows Update is a convenient feature used frequently by users to install updates not only from Microsoft, but also from third-party providers. However, they encounter a series of Windows Update error codes while updating. Windows Update Error code is one of them; it occurs when users try to install updates to their Microsoft Office — the Windows Installer discovers an issue during the process.

You see this error, and you realize the requested updates or automatic updates have failed. That way you will receive the best help there. Was this reply helpful? Yes No. Sorry this didn't help. Thanks for your feedback. I downloaded and installed 8 of 9 updates successfully in my computer which has Windows Vista Home Basic , but the important security update for Microsoft Works 8 KB failed, and I received Error Code , followed by a "Windows Update encountered an unknown error" message.

I tried to download and install the update several times, without success. I finally stopped trying to install the update, as I thought Microsoft would soon come up with a solution for the problem, and I would be able to install the update at a later date. I found out that the Microsoft Works program in my computer is really version 8. Could the difference in the version numbers of the Microsoft Works update and the Microsoft Works program in my computer possibly be the reason I received the Error Code , "Windows Update encountered an unknown error" message?

Janice M.