You may tried to update windows 7 using the default updater.It downloads the update from internet and installs it locally.If you want to update your friend’s pc,then you have to go online again.
To avoid this problem, Windows 7 can be updated offline using an autopatcher tool.so you can install it on any number of computers.
Using the autopatcher you can download the windows updates like downloading software from internet, later you can install on your system or your friend’s too.You can also select updates necessary for you instead of downloading all.
This also avoids the risk of being blocked by windows for genuine version.
Run the installer and start downloading update files.
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