Sometimes a particular update gets stuck, and is offered repeatedly.
If you can identify the # of the update that you are seeing I can offer
specific advice.
Generally, the process that is worth trying is to download the update
manually from Microsoft, save it to the desktop, and run it from there to
install it. Some of the time that succeeds, and when it does not, it is
easier to find the log file from the install, which may give some clues
about what is going wrong.
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