By Emily / Last Updated November 26, 2019

Can I copy OS from one drive to another?

My Windows 10 OS runs on a SanDisk HDD, but it begins to fail. So I bought a new SDD hoping that I would be able to clone the OS from the failing hard drive to it. But I have never done this (copying OS from one drive to another) before. So any one can tell how can I copy OS from one drive to another? Or is there any great OS cloning software I can make use of? Thanks!

- Question from

When you will need OS cloning software?

OS cloning software, as its name implies, is to clone the original operating system from one disk to another storage device such as a hard disk drive (HDD), solid-state drive (SSD) or other external hard drives. Then you can obviate the need to reinstall OS from scratch, which can be a tedious process especially when the Windows activation keys are not available any longer. Typically, you will need an OS cloning tool in the following three major situations:

  • Upgrade small disk to a larger one: if your current system hard disk is too small to hold extra new programs, you can clone OS to a larger drive to get more space.

  • Replace the failing OS disk: when you find your OS disk fails now and then, it is better to clone the OS to another disk and swap out the old one in case of the OS hard drive crashes someday.

  • Install OS onto SSD drive: when you plan to install OS on SSD drive to enjoy faster read and write speed, you can directly clone OS from HDD to SSD instead of performing a fresh installation on the solid-state drive.

  • Make a system backup: since the system drive is easy to get damaged due to corrupted MBR, disk errors, virus attack, etc., it is wise to clone the OS partition to make a backup before system crashes.

What’s the best free OS cloning software for Windows 10/8/7?

As mentioned above, there are several situations in which you need to clone OS to another disk, so choosing a proper OS cloning utility is quite important. When you Google it, different types of hard drive cloning software will pop out, to ensure a rewarding and successful result, we would like to recommend using AOMEI Partition Assistant Standard.

This software is completely free without any bundled software. To clone Windows 10/8/7 OS from one drive to another hard drive, it provides the following two methods:

1. Disk Clone Wizard: clone an entire OS hard disk (including OS partition and other data partitions) to another hard disk.
2. Migrate OS to SSD Wizard: clone only OS partition from one disk to another one (HDD or SSD).

No matter which method you choose to copy OS from disk to disk, you can enjoy below benefits:

✌Copy OS to a smaller hard drive as long as the available space on the destination disk is equal to, or larger than the used space of the current OS partition or disk.
Align partitions on SSD during the OS clone process to optimize the data writing and reading performance of the destination SSD.
✌Boot your OS from the target disk after the OS clone since it will copy everything necessary for system startup.

2 Methods to clone OS from one hard drive to another

Now you can press the button to free download the OS cloning software and learn the earlier-mentioned 2 methods to clone OS to another disk in Windows PC. Then choose one based on your requirements.

Before proceeding, please pay attention to:
● Ensure the destination disk has an unallocated space, equal or larger than used space of OS partition or disk. If no unallocated space, create one by deleting or shrinking existing partitions.
Back up everything important on the destination disk because this process will delete all data inside.
● Check whether there are some bad sectors or errors on the original system drive.
● The freeware only supports cloning OS from MBR to MBR disk. If you need to copy OS between MBR and GPT disks, you can upgrade to AOMEI Partition Assistant Professional.

Method 1. Copy only OS partition to another drive

If you just want to clone OS partition from one disk to another, this method is a better choice.

Step 1. Install and run the AOMEI Partition Assistant Standard. Then you can get into the main interface of this software; click "Migrate OS to SSD" on the left side under Wizards. In the pop-up window, click "Next" to continue.

Migrate Os To Ssd

Step 2. In the next window, choose an unallocated space on the destination HDD or SSD, and then click "Next" to go on.

Select Disk Space

Step 3. In the pop-out window, you could resize the partition, assign a drive letter to it, or just keep default settings and click “Next”.

Resize Partition

Step 4. A helpful note about boot problem will appear. Read it in case you might meet some boot failure problems after OS migration. Then click “Finish”.


Step 5. Click “Apply” in the main interface to start transferring operating system to a new disk.


Method 2. Copy the whole OS disk to another disk

When you want to copy all data from OS disk to another hard drive, try this solution.

Step 1. In the main interface of AOMEI Partition Assistant Standard. Click “All Tools” and then choose “Disk Clone Wizard”.


Step 2. Choose a method to clone the OS hard disk and click “Next”.

Copy Methods


  • Clone Disk Quickly: clone only used space to the target disk, so the target disk can be smaller than the total space of source disk but must be larger than its used space. This way allows for cloning larger disk to smaller disk.

  • Sector-by-Sector Clone: clone every sector to the destination disk, no matter it is used or not. So the target disk must be larger than the source disk.

Step 3. Choose the original OS hard disk as the source disk.

Source Disk

Step 4. Choose the destination disk. If it is an SSD drive, tick “Optimize the performance of SSD”.

Target One

Step 5. If you select “Clone Disk Quickly” above, you can edit partition size on the destination disk in this window.


Step 6. A boot note will pop out. Read it carefully and click “Finish”.


Step 7. Click “Apply” and then “Proceed” to commit the pending operation.


One more step: boot from the destination disk

After copying OS from one drive to another via the free OS cloning software, now you need to insert the target disk into your computer and reboot it, change the boot order to set the PC boot from it:

Step 1. Start your computer and keep pressing ESC, F1, F2, F8 or F10 during the initial startup screen to enter BIOS setting.

Step 2. In the Boot option, select new HDD/SSD as the new boot drive and save all the changes.

Step 3. Finally, restart the computer, you should be able to see Windows OS running on your new disk without any problems.

If the cloned hard drive or SSD won't boot, you might need to check whether the system files or the Master Boot Record of the current system drive are intact.


So, with this powerful OS cloning software, you can easily copy OS partition or entire OS disk to another hard drive as you wish. Moreover, it is far more than a OS copying utility, and it is also a free MBR to GPT converter (allowing you to convert disk between MBR and GPT without deleting existing partitions), an SD card repair tool, MBR repair tool, and more.

To enjoy those amazing disk management functions on Windows Server computer, you can try AOMEI Partition Assistant Server.