Don't have one.
Most Windows systems are set up to connect and update Microsoft software using a built-in updater. You should find it in the "start" menu under "Microsoft Update" or similar. There is an "Automatic Update" program under "Control Panel" to manage this function. You can even set it up to do everything by itself, but I've got it set to "notification" only, as I like to see what's going on first.
The updater version I'm using also updates Office stuff.