How can I backup my Windows 7 update files in order to install these updates on another PC with Windows 7 in offline mode and without connecting to internet?
have a look at this: http://www.wsusoffline.net/
thanks, never thought something like this was out there
Windows 7 (and Vista) update differently than previous Windows editions.
The downloaded updates *cannot* be reused in 7/Vista because they come
down as packages that compromise the updates. Component Based Servicing
is the mechanism that installs them, stores previous versions of files,
etc. That mechanism did not exist prior to Vista.
So, the only way you can reuse updates is to manually download them from
either the MS Download Center or the Microsoft Update Catalog and save
them for future use.
Sorry, but that's the way updating Vista/7 goes nowadays.
Microsoft Update Catalog
Microsoft Download Center
"Googling" I've found this link: http://www.technize.com/2-ways-to-download-windows-7-updates-for-offline-installation/
I hope it may be useful.