I continuously get this error: "Code 646 Windows Update encountered an unknown error" when I try to install these updates: Security Update for Microsoft Works9 (KB2092914) Update for Microsoft Office Outlook 2007 Junk Email Filter (KB2279264) Security Update for the Microsoft Office System (KB2277947) Security Update for Microsoft Office Outlook Security Update for Microsoft Office Word 2007 (KB2251419) I've re tried many times. I have put the MS Office CD back into my PC and got a "successful" when I ran a "Repair". I found a comment on the FAQ page that provided a link to what I thought was one of the update specific downloads, but I got a message that that update had been installed already.

Hi, Please refer to Error code "0x80070646," "646," or "1606" when you try to install Office updates to resolve the issue. Regards,Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.