There are various reasons you might wish to replace your hard drive with a larger one. You might be running out of space on your drive, and in the case of a laptop you almost certainly don’t have the ability to add a second drive. Or you might be getting signs that your old drive is about to fail, and wish to move your data across before it does so. In fact, with laptops of more than a couple of years old which have seen heavy use, moving to a new hard drive may be a very good idea because the newer hard drive will be less likely to fail, and you will be left with a snapshot of the current state on your old drive, as well as the opportunity to increase the available space.

The way to copy the data to the new drive while retaining a working system is to use backup software such as Acronis TrueImage (other software is available, including free software, but we found Acronis is reasonably efficient). You should make a backup of the entire hard drive (which probably contains multiple partitions) onto an external hard drive. Your backup software will probably create a single large file containing all the data, so probably needs to be formatted as NTFS (or HFS/HFS+ in the case of Apple systems) rather than FAT.

Once you have the file you can use your backup software’s Restore function to restore the data onto your new, blank hard drive. The easiest way to do this if you just have the one computer is to obtain a SATA USB caddy which enables the drive to be connected as another external drive. Once you have completed this step then the new drive should be able to function as a replacement internal drive in the computer.

However, in many cases (including Acronis) the new drive will appear as the same size in your system, because even if the drive itself is larger, the partitions on the original drive will be exactly replicated. If you are happy to have an additional partition on the drive, appearing as a different drive letter, then you use the Windows Control Panel (or Mac equivalent) to create a new partition. However, if you wish to have a single large partition, then you need a way to enlarge the existing partition to occupy all the free space on the drive.

We have had trouble finding reliable Windows tools for this step. However, GPartEd, a free tool which comes with Linux installations such as Ubuntu, can be used to re-size the partition very easily and quickly. NB This is a potentially dangerous step which risks Total Data Loss and it is important to ensure you have a good working backup before undertaking this step. In this case, we have the old laptop drive to fall back on.

So, if you connect the new drive as an external drive to a Linux system (which could in fact be your usual Windows system with Ubuntu or Knoppix running from a USB key or DVD, available for free online), run GPartEd, and resize the partition to occupy the free space, please ensure that you select the “Align None” option to ensure compatibility with Windows.

Another issue is that if any bad sectors are located on the hard drive being resized then GPartEd will not be able to resize the partition, but will not do any harm to it either. There are ways to force the resize in these cases but it is beyond the scope of this article, and we hope that your brand new drive will not contain bad sectors.

Once the re-size has completed, you should now be able to simply insert the drive into your computer as its new main internal drive, with the system unchanged except for the new free space on the drive.