I.P. address?

All computers connected to the internet have a special or unique number. This is known as an I.P. address. Such addresses are issued by I.C.A.N.N.. This stands for the International Corporation of Assigned Names and Numbers and is responsible for, and presumably capable of, ensuring the uniqueness of your, and everyone else's I.P. or Internet Protocol address.

Recovering System After Upgrade

Usually upgrades are binary: either they work or they don't. Actually, my experience with SME upgrades has been very good: I've only had a very few where the upgrade process didn't work at all. In those cases, you install new, apply all applicable blades, and then restore from backup. That's annoying, but fairly simple.

Alien Intruders!

You probably didn't casually invite, or extend a formal attendance request to, these undesirables known as viruses.