Just did this on another laptop and it took over a week for all the updates to download and install.
My answer. About a week or two.
The fastest way I know of is to let it update and when the machine is done, create an image that I can restore to. That takes about 20 minutes here.
I just installed Windows 7 pro into a newly built computer. After getting the latest drivers for my components, I tried to get the latest update from Microsoft. First I got an error but it was because my date and time was wrong. Now it shows that it's looking for updates, but this has been going on all day. Does it really take 24 hours to get the latest update? and if it doesn't, is there any other way to get the latest update?

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