External USB drives are a great way of creating a handy and portable backup. If your drives start giving you trouble, you might conclude that the hardware itself is to blame -- but be sure to check the connecting USB cable as well.
While running a manual backup onto a USB hard drive recently, my drive kept connecting and reconnecting, losing the drive mapping in the process and rendering the backup software useless. At first, I suspected that the disk itself might be at fault, but then I decided to try connecting it using a different USB cable, and the whole backup ran without a hitch.
The offending cable (pictured) promptly got sent to the bin. While there were no obvious flaws in it, there's no point hanging onto an item that's clearly causing trouble, especially when it's so cheap and easy to replace.
Naturally, no backup system should rely on a single technology. A combination of a networked backup drive, some cloud storage and some additional USB drives should protect you from most eventualities. If you do just want to use external drives, at least have a pair of them. Learn more with our in-depth backup guide.