What the heck is Bill talking about this time?
You may be thinking something along these lines right now, so I had better explain what that headline is all about. If you use a single computer running Outlook to access your email, things are simple. But suppose you have a desktop computer and a notebook, both running Outlook and both connected to the same account or accounts.

Now things can get messy.

Log on and work with your email or other Outlook data from the desktop, then try logging on with your notebook. Depending on all sorts of factors, what you see in Outlook on one machine may not match what you see on the other. I don't have space to describe how this happens in detail here, so if you haven't seen this kind of problem yourself, trust me, it happens and it is a major pain.

Now throw in your smartphone, your machine at home that you use to check your email right before bed (don't deny it) and the time you needed to log in from Sally's machine in the other office because your notebook battery was dead, and the situation could get really ugly really fast.

In a corporate environment, Outlook is usually connected to an account (called a mailbox) on a Microsoft Exchange Server (we just call it Exchange). In these cases, your Outlook data lives on Exchange and when all your computers and mobile gizmos connect to that mailbox, they all see the same data and automatically stay synchronized.

This is all very cool and mostly works really well, and makes life a lot easier when you are using a mailbox on the Exchange Server. Even better, someone regularly backs up the Exchange Server. When was the last time you backed up your desktop and notebook computers?

Too bad your personal accounts aren't on an Exchange server.
As I'm sure you've guessed by now, you can get an Exchange account for personal use. A Hosted Exchange Mailbox is an Exchange mailbox that resides on an Exchange Server located, well, somewhere else.

Outlook connects to a Hosted Exchange Mailbox across the Internet, giving you many of the same benefits as you have for your corporate accounts. You can connect to your mailbox from different computers and gizmos and be confident that they'll all stay synchronized. And you can be confident that someone is backing up all your data for you.

The specifics of hosted Exchange services differ, but the basic idea is the same. To illustrate what it is like using one of these services, I'll describe 4SmartPhone, the hosted Exchange service I use.