DoYourClone for Windows is on GOTD today, so thought it might be useful to finally post something I’ve been thinking about writing for a while now.
Computer storage, e.g., hard disks, optical discs, SSDs, USB sticks, memory cards etc., require a file system, which basically is a standard to read, write, and basically interpret the raw data that’s stored. Windows mostly uses NTFS, the older FAT32 [mainly for boot partitions], XFAT [mainly things like USB sticks], EFS [Encrypted File System], and the upcoming ReFS [a newer version of NTFS that Microsoft has been working on for years].
While a file system like NTFS stores info on stored files in its own tables, partitions are also required to keep track of things… data is written to a conventional hard disk in small chunks, which in turn are strung together to contain each file, and partition tables keep track of which chunks of data make up which files, along with their physical location on the platters in a hard disk. SSDs, memory cards, USB sticks etc. don’t work exactly the same way as conventional hard disks but emulate the way hard disks work for the sake of compatibility. [It’s possible ReFS, once it’s mainstream, will treat those types of storage natively in a way that’s more efficient than the current emulation.]
Each hard disk, SSD etc. requires one partition, but can have several more. Each copy of an OS requires it’s own partition, but beyond that you might think of partitions as kind of like drawer dividers, that make storing whatever more organized & efficient. Each partition has a maximum size – it’s usually the entire disk if there’s just one partition, while multiple partitions divide up the total amount of storage, e.g., two 500GB partitions on a 1TB drive. Note that not every computer OS recognizes more than one partition on some kinds of data storage – Windows for example doesn’t like more than one partition on memory cards or USB sticks, though they are quite possible.
Complicating matters, there are two main types of partitions, the older MBR and the newer GPT. The GPT partition spec is designed to be quite compatible with MBR partitions, and for the most part, while there are differences, like a GPT partition’s ability to have many more partitions on a single hard disk, in *most* cases the 2 partition types are interchangeable. The exceptions to that rule mostly have to do with the computer’s BIOS. Simplified, the BIOS takes stock of the various components, sort of ties them together, and works as the interface between the OS and hardware. The BIOS used to be individually hard coded, but nowadays usually make use of a standard called UEFI, running a specialized OS similar to Linux. For compatibilities sake many can also emulate the older [called Legacy] type of BIOS. While GPT partitions Are Not required for UEFI to work, Many BIOS will jump into UEFI mode when they see a GPT boot disk [the disk with the boot loader code required for the OS to start], or Legacy mode when they see a disk that’s MBR. The other main exception is the newer NVMe type of SSD drives, which you generally want to format GPT.
Because of possible BIOS quirks, you’ll usually just stick with the type of partition(s)/disks that already exist on your device. You can convert an MBR disk to GPT using a partition app like AOMEI Partition Assistant [a regular GOTD], usually if you’re upgrading your PC but re-using the hard disk with the preexisting copy of Windows. You can also copy data from a MBR disk to a GPT disk, clone an MBR disk to GPT disk, and restore a backup image of an MBR disk to a GPT disk, depending on the software you use – Mileage Will Vary, so Test before you commit to a change. That all said, the newer GPT is better, so if/when you have the opportunity to choose, choose GPT.
Partitions can be hidden, usually just meaning they don’t have a drive letter assigned and don’t show up in Windows Explorer, or they can have a drive letter and show up in Windows Explorer like a separate disk or drive. There are exceptions… there are some partition GUIDs that Windows can use to restrict access, and Microsoft used to use those with the boot partition for Windows 10, but I haven’t seen that for a couple few years now. In Windows the main tool you use to deal with disks and partitions is Control Panel -> Admin Tools -> Computer Management, and then on the left of the app’s window, Storage -> Disk Management. If you use external USB drives/sticks etc. you might become quite used to using it, e.g., to add a drive letter to a newly inserted USB stick. Windows also includes a command line utility called DiskPart, which can do some stuff most 3rd party utilities cannot, but it’s a bit of a pain to use. Windows also assigns a unique identifier to each partition, which can be an issue if you ever have a duplicate, say from cloning. As long as the duplicate Is Not the boot disk [the one with the boot loader for Windows] you can select it in Disk Management, right click the header on the left, and select online, which should create a new unique ID. If it’s the boot disk it is possible to change, but more involved than the scope of this post.
One of the ways you’re more likely to deal with partitions has to do with Windows 10 itself… the usual installation is on a GPT disk with a hidden FAT32 partition holding the boot files, a small hidden partition for Windows use, the normal Windows system partition, and a hidden Recovery partition with the files to recover Win10 stored in a .wim [a Microsoft image file format] file. When you perform a Win10 version upgrade that’s a full (re)install, you’ll occasionally get a 2nd [or 3rd, 4th etc.] Recovery partition. At 500GB each that can be unwelcome, but unfortunately there’s not a great solution. If you delete that partition before upgrading, it might not replace it with a new version. To delete one Recovery partition, you have to add drive letters, figure out which one’s the old version, delete it, then enlarge the Windows partition to take up the freed space, which can 1st involve moving the remaining recovery partition to the end of the disk – the old Recovery partition is often the last one. Or you can just delete any & all Recovery partitions and reclaim that space – a decent enough solution if you regularly perform image backups.
You can also add partitions to make managing your files, and Windows, more efficient. The first step is to free up the disk space for the new partition, selecting one partition [usually the Windows partition] and defragging it, so that all the files are moved to the beginning of the partition. Then you shrink that partition to create the free *unallocated* space and create a new partition in that space. If your apps or files are on a partition separate from Windows, you can create a partition image backup of whichever partition irrelevant of any other partitions, so you can back up your files, or Windows as needed, and the backup will take up less space because you skipped the stuff that hadn’t changed since the last backup. Recovering your files after a mishap is also easier. Note that many of the default user and public folders like My Documents can also be relocated to another partition or disk – right click the folder, select properties, then *IF* there is a location tab in the properties dialog, select the new location that Windows will use from then on. That adds a bit of safety, e.g., if you have to recover or reinstall Windows, your stuff is still separate & OK – telling Windows setup or recovery to preserve that stuff doesn’t work 100% of the time.
Now Cloning… Windows itself uses special files and file types so you can’t simply do a copy/paste to transfer everything to another disk &/or partition, though you can certainly use that with other files and file types. But it’s not efficient, even if you use one of the rapid file copy utilities, because Windows deals with each file, one at a time. A disk/partition image backup, & cloning, works with raw data, not caring really what that data is or what files it belongs to, so it’s much faster. An image backup app stores that raw data in a [usually mountable] archive that can be restored anywhere there’s enough room. Cloning skips the storage step. Personally, I generally prefer working with image backups because they give you more flexibility.
Say I’m going to replace a PC’s or laptop’s single hard disk… In this case it’s a tossup, where I can replace the drive, boot to the backup app’s USB stick, then restore a backup from an external drive, or I can clone the existing drive to the new one mounted in an external drive dock, then swap drives. But lets say my PC uses a conventional hard disk, and I want to add an SSD for Windows… Ideally you should only use ½ the capacity of an SSD, so lack of space could be a problem, particularly if the SSD was a cheap 120 or 240GB drive. I’ve set it up so most of my software was installed to another partition, and the same for folders like My Documents. All I really need to transfer to that new SSD is the Windows partition, which I can easily do restoring a backup image of that partition. I *might* have to do some re-assigning of drive letters, so that software that was installed to the D: partition is still on the D: partition. I could restore a backup of the Boot partition, setting the boot drive order in the BIOS so the new drive is 1st in line, or because Windows boot loader [BCD] can be a bit finicky, I could use EasyBCD to change the drive in the boot loader where Windows lives to the SSD.
Some software will let you clone just the partitions you want, but I feel safer restoring a backup, because I know if something goes sideways, I can always put things back the way they were before I mucked them up. I also want to note that there are new types of SSDs on the market, plus the NVMe [M2] drives, and they can make booting to a preexisting copy of Windows not work. In addition, some devices nowadays make getting into the BIOS & changing the boot drive order difficult, and Windows 10 can interact with the BIOs to change the boot drive order, and even what drives are available to select. It may be necessary in some cases to use the boot repair utility in something like Macrium Reflect paid version – AOMEI has a similar tool, though I’ve never tried it.