The Mac user's guide to Time Machine

How to keep files safe and what to do when the worst happens

Recovering files from Time Machine is easier than you think…

Backing up lots of files is relatively easy, and finding individual files that you want to restore is almost as simple. Time Machine's great strength lies not only in the fact that it's easy to use and works incrementally, only backing up files that have been added or changed since the last backup, but in the way that it provides access to those backups.

With more basic software, you usually have to pick your way through an arcane set of options to look for the items you're after. With Time Machine however, you can navigate in a much more intuitive way.

There are many possible situations in which you might want to get hold of an earlier version of a file or folder. The most obvious would be when you have accidentally or deliberately deleted something but then later find that you need it back; or, where you have changed a file but then realise you want to get that original version back again.

With Time Machine you're able to access a file or folder at every point at which it's been backed up. And since the backups are incremental, it will only have been backed up when it has been modified in the period between two backups. So provided that you let Time Machine run regularly, you should be able to access items as far back as their creation or first backup.

By choosing to enter Time Machine from the menu bar icon, which you can choose to show in Time Machine's preferences, you will invoke the Time Machine interface. This causes the Desktop to slide away and be replaced with a screen depicting the various stages of the currently selected folder going back through time.

Along the right-hand side of the screen you will see a timeline stretching from the present back to the first backup, complete with dates, and two arrows to navigate back and forth in time. If you run the mouse over this timeline you will see that it behaves a little like the Dock, magnifying itself to reveal more details about the time period you have selected and displaying specific dates for any backups that you mouse over.

Click on one of these to jump straight to it. A bar along the bottom of the screen shows you the exact date and time of whatever backup of a folder you are looking at.

To use Spotlight within Time Machine, you can type a search term into the search field in a Finder window and hit the back arrow to make Time Machine search through its backups for that term. If you don't know exactly when you last deleted or changed a file, you can use the back arrow to automatically travel through time to see when that folder was last modified.

Once you have located an item, you can use Quick Look by selecting it and hitting [Spacebar] to get a preview of its contents. You can't open items directly in Time Machine view, but you can preview them by using this method. In the case of music and movies, Quick Look will actually let you play them back.

iTunes

Once you've identified an item you want, you can restore it by selecting it and pressing the Restore button at the bottom right. The file will then be copied to the Desktop or the current instance of the same folder it's located in, if it still exists. If two items in the same folder are going to have the same name, you're prompted to keep only one or both.

In OS X 10.6 you can right click on an item in Time Machine view and choose Restore to… which will let you choose a destination. For users of OS X 10.5, make sure the 'action' or 'gear' icon is present in your Finder window's toolbar. You can enable this by choosing View > Customize Toolbar.

This contains an option called Restore to which has the same effect. The item will remain as part of the backup, but now will also exist in the present, and so will be included in the next backup.

It's possible to restore several items or several folders within a folder by simply multiple-selecting them, holding the Shift or Command keys while clicking to choose them.

The right-click menu for one or more items in Time Machine also has some other functions. There's Open, which activates Quick Look, Get Info to reveal item information, and some deletion options.

Delete Backup will remove that instance of that item from the currently selected backup, and Delete all backups of the file will identify any instances of that file that exist in any of the backups on that drive. This is useful for saving space when big items are using it up and are no longer required.

Restore within Apple apps

Time Machine also works within some Apple apps Being able to recover files and folders is great, but many applications store their information in different ways than simply files with names in the Finder.

Applications like Address Book, Mail and iPhoto, for example, use databases of information and it's not so straightforward to pull a single email, contact or photo out of a backup like you could with a folder or a Word document, because they're contained within a larger database.

Luckily though, Apple, having designed all of the software in question, has addressed this and made it possible to access certain restore features of Time Machine from within these applications. Although you could navigate to the database files using the regular Time Machine view, this method isn't actually all that helpful because it wouldn't show you the information in any kind of usable form.

And by restoring that information to the desktop you would still have to open it in the relevant application to view it, which can cause problems with overwriting current data.

The solution is really quite simple and involves booting the relevant application and then, with it still in the foreground, invoking Time Machine either from the Dock or the menu bar.

What happens then is that Time Machine's interface appears, only instead of showing the Finder and its windows as normal, it shows the application's window. You can then move back and forth through time and for each backup you will see the relevant data that existed in that application, at that point.

So in Address Book, for example, even if you have deleted some contacts, you will be able to go back in time while staying within Address Book's interface and restore one or more contacts back to the present. In Mail, you can do the same and restore mailboxes or individual email messages that you had since deleted.

Time Machine will avoid duplicating mails by creating a separate mailbox within Mail for the recovered emails. In iPhoto '08 or later, you can do the same and restore photos from previous backups. Even GarageBand from version '08 onwards now supports Time Machine, so if you open a GarageBand project and invoke Time Machine you will be able to revert to an earlier version of a project, as long as it was backed up.

There are a couple of caveats to this, even though on the whole it's very useful. The first is that you cannot restore these things to an alternative location like you can with files and folders; they have to be restored to the current database folder of the application in question. As such, in some cases they may overwrite current data, unless you keep your eyes open.

The solution to this in GarageBand is to duplicate the current project file prior to restoring an older one, so that you have a copy of both.

As we have noted, Mail creates a separate mailbox to avoid confusion. iPhoto will prompt you to overwrite any images that are identical to the ones you're restoring and so gives you the choice whether to do so or not. Address Book will ask if you want to add the selected cards to the database and will warn you if the card is a duplicate of an existing one, giving you the option to review the conflicting information and amend it if necessary.

So as long as you understand what you're restoring, there should be no problems with overwriting existing data.

Another minor quirk of this way of working with Time Machine as opposed to the regular files and folders approach is that sometimes, if you enter Time Machine with an item selected that wasn't present or was excluded when some of the backups were done, those backups will be greyed out in the timeline on the right and you won't be able to select them.

If for example you have recently created a mailbox in Mail and then enter Time Machine with that mailbox selected in Mail, only backups made since that mailbox was created will appear in white as normal; the earlier ones will be greyed out.

You should, however, be able to return to Mail and select another, older mailbox and then back in Time Machine view, the previous backups associated with that mailbox will be available to select.

Other applications do not at present integrate with Time Machine in this way, so if you enter Time Machine with another application in the foreground, it will simply slide from view and the regular Finder view will take its place.

Time Machine integration with these key Apple applications might seem like nothing too exciting on the face of it, but in fact it's incredibly useful. You have always been able to back up a load of information in one go – your Mail database or photo library, for example – and then dig through them in the Finder later to try to locate and extract individual mails, pictures, contacts and so on.

But that can be a long and slow process, especially compared to the convenience of simply jumping into Time Machine within an application and being able to search all its backed up data in the same view you normally see when using the application. All the formatting remains intact and of course you can use Spotlight from within Time Machine to search.

In fact, Address Book, Mail and iPhoto all have their own search fields that still work in Time Machine view, so you can quickly search any backups directly from inside the app, making it easy to find data from even the biggest library of mail, pictures or contacts.

At present, these are the apps that integrate with Time Machine, but hopefully Apple will in future add this level of backup support to other apps.