Keep files and settings safe with PC backups

A 320GB 3.5in disk currently costs around £30, while a 2.5in disk of the same capacity and manufacturer costs £65. A high-capacity USB flash memory key provides a third option and they are small enough to attach to a keyring, though these remain extremely expensive in comparison ­ a 64GB memory key, such as Corsair’s Flash Voyager costs around £130.

Some external disks use a technology called Raid 1, also known as mirroring. This uses two hard disks of the same capacity but appears in My Computer as a single drive. Every time you save a file to the drive, two copies are created and saved to the individual disks.

Some large-capacity external disks offer Raid as an option. So, you can have a 2TB product that provides the full 2TB, or flick a switch to Raid 1 to get half that capacity but more peace of mind because if one disk fails, a full copy of it is on the other. If you choose a disk with Raid 1, you need to choose a mode and stick to it ­ – if you change from normal storage to Raid 1 or vice-versa, the disk is reformatted, deleting everything on it.

Western Digital’s Mybook Mirror Edition, Verbatim’s 2-Disk Raid and Lacie’s Hard Disk Max provide 2TB of storage or 1TB of Raid 1 storage for around £200. The Verbatim model also has an eSata socket.

Something to bear in mind is that, while Raid 1 protects from physical error, deleting a file will wipe it from both disks instantly. Similarly, any external hard disk becomes susceptible to malicious attack when connected to a computer, so a resident virus could destroy both the original and backup copy of a file.
While not particularly common, some computers have a Raid 1 system of disks built in inside the case. It’s vital to note that this is not a suitable way to back up the contents of a computer, as every time you save, change or delete a file on one of the disks, the action is ‘mirrored’ on the other disk. Raid 1 disks insides PCs are suitable for guarding against one of the discs failing but if a virus, for example, damaged files and documents on one Raid 1 disk, the calamitous effects would also harm its twin.

There’s one final Raid mode that’s worth mentioning because you might see it advertised or mentioned in a hard disk manual. It’s called Raid 0 and distributes the files across the two disks in a way that makes it slightly faster to open or copy files back to the computer. It means you get the full storage capacity from the two disks but no copy to fall back on if one disk fails.

Automating backups
At its most basic, dragging and dropping selected files and folders to an external disk will provide you with a backup of your personal documents, Internet Explorer favourites and saved games. However, it’s this kind of manual file operation that makes backup laborious. Problems can easily arise if documents are open during the copy operation.

Windows has its own tool to automate the process. Vista has the Backup and Restore Center, which you’ll find in the Control Panel. Tell it what types of file and where to back them up to and it will do the rest on schedule. Windows XP’s backup system is more limited, though XP users need look no further than S yncback. A free version is available here (this link will prompt you to download the installation file) while the far more powerful Syncback SE costs £20. As well as scheduled backup, Syncback offers a synchronisation mode that ensures two folders in separate locations are kept constantly identical.

You can also buy specialist disk management and backup software that takes a complete copy of your hard disk and stores it on an external hard disk. The file it creates is called a disk image, and can be used to restore Windows, applicat ions, folders and documents after a serious problem. Applications such as Norton Ghost and Acronis do this and include a time-saving feature called incremental backup. This simply means that instead of taking a whole new copy of the hard disk at each backup, the software simply copies files that have changed or been added.

Clickfree provides another way to effortlessly back up files to external disks. A Clickfree hard disk contains a secondary ‘virtual’ disk that stores its own backup software ­ – as soon as this is connected to a PC, it will back up selected folders automatically without the need for any software to be installed on the PC itself. This is especially useful if you use more than one computer. You can also transform any external hard disk with a USB socket into a Clickfree with a Clickfree Transformer adapter. The disks are available in various capacities starting at about £40, while the Transformer costs about the same.