Update error 80070643

I get Windows Update error 80070643 when trying to install a security update
in Vista x64 home premium for the media player. The suggested office related
solution does not seem to apply and definitely does not work. An attempt to
install via safe mode did not work either.

Here are the details:

Security Update for Windows Vista for x64-based Systems (KB936782)

Installation date: ‎8/‎30/‎2007 9:55 AM

Installation status: Failed

Error details: Code 80070643

Update type: Important

A security issue has been identified in Windows Media Player that could
allow an attacker to compromise your Windows-based system and gain control
over it. You can help protect your computer by installing this update from
Microsoft. After you install this item, you may have to restart your computer.