I was looking for an answer to the same problem. Same version number Vista.
Same error code 0x8024400a when I check for updates for both Vista and
> Hi to all,
> anybody have this problem?
> When i click on "Check for Updates" in Control Panel - Security - Windows
> Update window, the system perform a check for 2-3 seconds and reports the
> error 8024400A. On the help guide, there is nothing.
> How can i fix it?
> I cannot download/install Vista and/or Windows Defender updates.