How to Copy C Drive to External Hard Drive Windows 10?

Why copy C drive to external hard drive?

The C drive, commonly referred to as the system drive, is the primary hard disk partition that houses the operating system, programs, and system data. When you want to clone C drive to an external hard drive, it implies that you wish to clone the operating system to external storage devices. Users typically copy C disk to external hard drive for three reasons.

▶ Reach better PC performance
When the PC speed degrades with time owing to various caches, apps, data, and so on, you may clone the system disk to an external drive and boot from the drive to boost computer performance, particularly on an SSD.

▶ Create a portable Windows
If your computer fails to boot, you may need to buy a new one, or directly use your old WIndows on another PC to finish your work in a rush. In this case, you may wish to clone the C drive to SSD or HDD as a portable Windows before purchasing the new computer, or using your Windows anywhere you need.

▶ Upgrade storage
Many users would like to use SSD on the PC as the new system disk. If you don’t want to reinstall Windows and your apps, you can copy C drive to your new disk and keep other things on your old disk to upgrade your disk storage capacity quickly.

How to copy C drive to external hard drive in Windows 10/11?

If you just need to keep some important data files on a C drive, then you can directly copy and paste those files from your C drive to another drive. But, C drive can’t be copied as files or pictures. You need to use a specific partition/disk cloning tool to complete this work. This kind of tool will not only copy your files but also the partition data and all system-needed parts that users won’t see on the target disk.

AOMEI Partition Assistant Professional is an excellent option in all such tools. It can aid in cloning the operating system, disk, and partition. This tool enables the upgrade of a hard drive to a larger one as well as the cloning of an HDD to an SSD for improved performance. Furthermore, it can resize partitions during the copying process.

Now, we can prepare for copying C drive to SSD/HDD.

Preparations

To protect your data and your OS, we need to know some details.

1. Back up your system in advance just in case something uncontrollable occurs during the process such as a power outage.

2. Shrink your system drive or disk to make it as small as possible and better fit on the SSD since SSD drives usually have less space than HDDs.

3. Connect the SSD drive to your computer and make sure it is detected successfully. If you are using a desktop, you need to open the case and hook up the SSD to motherboard. If your computer is a laptop, you have to connect the SSD via a USB port and the SSD should be put in a USB adapter.

4. All data on the destination disk will be completely erased

5. Please make sure the motherboard supports the EFI/UEFI before cloning to ensure it could boot successfully later if you will copy C drive from an MBR disk to a GPT disk or vice versa. Keep the original and target partition have the same boot mode. You can convert to MBR/GPT without deleting partitions on your disk with the relevant conversion function of this tool.

Steps: Clone C drive to external hard drive

Note: Copying C drive to another disk won’t make the target disk bootable. But if you just want to copy C partition, you can turn to the “Clone Partition” feature.

If you want to boot your system from an external hard drive, then after you install AOMEI Partition Assistant, then use the “Migrate OS to SSD” feature. Here are the steps.

Step 1. Open AOMEI Partition Assistant Professional. Click “Clone” on in the top toolbar, and choose “Migrate OS”.

Step 2. Choose an unallocated space on the SSD drive. If there are partitions on it, tick "I want to delete all partitions..." to generate unallocated space and click “Next”.

Step 3. In this window, you can resize partition as you need, then click “Next”.

Step 4. A note on how to boot from the destination disk will appear, read it carefully and click “Finish”.

Step 5. Click “Apply” to commit the Windows system clone to SSD operation.

After the OS migration, you need to enter BIOS to change the boot order to your target disk.

To sum up

It’s not quite difficult to learn how to copy C drive to external hard drive in Windows 10. We offer you guides about how to copy C drive and how to copy C drive to make OS boot on the target. You can select according to your needs.

AOMEI Partition Assistant makes it simpler to clone C drive. Besides the cloning features, you can also move installed apps, convert file systems without formatting, and so on. There is also the Server Edition of this tool to help Windows Server users efficiently manage their devices.