Reader W.R. Clark had a problem common to millions of us who carry work from the office to our homes, or vice versa; and who work in remote locations, or offsite or while traveling:

Fred: I have multiple computers, including work, home, and travel laptop. It's a real task keeping my documents, certain key files, favorites, E-mail, addresses, and calendar synchronized on all three machines. There seem to be numerous fast solutions to replication, backup, or saving an image, but an absence of simple solutions for synchronization (perhaps using an external hard drive as the common medium).

--W. R. Clark

Surprisingly, Windows has functional tools for exactly this problem, but they remain largely unused and unknown. Even people who have heard of the built-in tools usually haven't actually used them; or only used them in much earlier incarnations.

One of the tools--the Briefcase--has been around since Windows 95; the other--Offline Files--since Windows 98. Both are present (in newer form) in XP, and both can help solve the problem of keeping data in sync when it's worked on in more than one place or on more than one PC.

There's a boatload of commercial sync tools available, too, but it makes sense to at least try what's already built into Windows before springing for third-party solutions. Using the built-in tools may also help in cases where policy prohibits the addition of third-party utilities to a company PC.

Briefcase And Offline Files
Both Briefcase and Offline Files serve similar purposes: They let you take a special copy of files and folders from one place, work on them in another, and then more or less automatically merge the changes back to the original files at a later date. "Synchronizing" the files this way ensures that all copies of the files are kept up to date; and that file deletions are replicated as well. Thus, the data stays consistent in both locations.

Briefcase is specifically intended for transferring and synchronizing files between separate PCs. Commonly, the Briefcase is carried on a removable disk of some kind, such as a floppy or USB drive; but it also can work on PCs with a direct cable connection or a normal network connection. Briefcase is extremely flexible, and can be useful in almost any situation, from a Fortune 500 enterprise down to a small-office setup, or even for moving data between home PCs.

Offline Files is geared more toward transferring and synchronizing network files in instances where a PC is sometimes connected to a network and sometimes not. Rather than using the Briefcase approach of moving between different PCs, Offline Files lets a single PC keep working on local copies of network files even when that PC's disconnected from the network. We'll get into this more in a moment, but for now, note that the Offline Files approach is harder to set up and more restrictive in its application than the simpler, more universal Briefcase approach.

And, not trivially, Briefcase is the tool that would best help reader Clark, so let's start there.