Yikes, Microsoft’s Time Machine clone leaves out tons of important stuff

(Updated to include a way to unhide files and add them to a “library” for backup)

Basically, this post is a warning to anyone using the new File History backup program in Windows 8. The program is severely limited because it will only back up files in a few preset locations that can’t be expanded. If you have almost any third-party program that saves its own data, File History is leaving you exposed. There is a fix, but it takes a little mucking around.

In my case, for example, I have gazillions of email messages stored by the program Postbox. The mail is kept in a huge folder in my personal Windows user folder under PostBox’s own folder in the application data area. None of the stuff that your applications have saved here is backed up by File History — none. And you can’t add it, either.

Update: As several commenters have noted, there is a way to get this data added to the backup set. In the Windows File Explorer, navigate to your personal directory and under the View section of the ribbon bar, click for a check in the box called “hidden files.” Then a folder in your directory called AppData should be exposed. Right click on the folder and choose “Include in library…” and add the folder to one of the libraries which is backed up by File History. Phew!

All that File History will save by default are “files that are in your libraries, contacts, favorites, Microsoft SkyDrive and on your desktop,” according to Microsoft. That is a huge hole, especially if you don’t rely on the My Documents, My Pictures and other “library” folders set up in Windows. Even if you do, third-party programs that store their data exactly where they are supposed to will not benefit from File History unless you use the trick above to add them.

That’s a shame because File History is supposed to be Microsoft’s version of the drop-dead easy to use Apple backup program Time Machine. Both work behind the scenes to back stuff up on an automatic schedule without the user having to remember. And both give quick access to old versions of files within the File Explorer/Finder program. But you can set Time Machine to backup anything from just a few files to your entire disk.