By AOMEI / Last Updated January 15, 2021

Case: transfer OS to another hard drive without reinstalling

"I have an old 120GB hard disk drive, and now I want to upgrade hard disk by transferring the operating system to another hard drive without reinstalling everything because I am tired of the low disk space problem. It makes storing new data and installing new applications impossible. The most unbearable point is that the computer works at a very low speed. So is it possible to transfer OS to another hard drive without reinstalling?"

Why transfer OS to another hard drive?

Speaking of why transfer OS to another hard drive, there are two main reasons.

1. The system partition or entire disk is out of space. This is a very common reason for all computer users. In general, the disk comes along with your computer is very smaller. In addition, you may install many new programs and add a larger number of new files to your computer. At last, you will get a disk warning message.

2. The computer runs slowly and you get better performance. After using a computer for a period of time, you may find that your computer does not run smoothly as before. Then, you may want to transfer the entire drive to larger hard drive or directly move OS to SSD.

Best OS cloning software to clone OS to another drive

Transferring OS to new hard drive involves complicated conditions and configurations. Many users have reported the disk won't boot after clone, and this isn't the only case you may encounter during the process.

To ensure secure boot, the most important thing is to choose a proper disk cloning tool, which can transfer all boot required drives and files to the target disk.

The reliable OS cloning software - AOMEI Backupper Professional, has been regarded as the best strategy in resolving the problem of "clone OS to another hard drive". It provides two ways for successfully cloning, System Clone and Disk Clone.

System Clone: It lets you transfer OS to new hard drive with the System Clone feature. All system related drives like system reserved partition or UEFI partition will be cloned simultaneously. Further, system customized settings, personal files and installed programs on the system drive will be copied to target new drive as well. In that case, you could get the similar Windows operating environment.

Disk Clone: It also supports transferring operating system from large hard drive to smaller drive, as long as the target space is sufficient for copied stuff. This technology is set by default. If you want to copy every sector of selected system drive, usually the C: drive, to the target, you can specify sector-by-sector clone.

With the help of such a powerful cloning tool, let’s see how to accomplish the OS moving task in detailed steps.

How to move OS to new drive in Windows 10/8/7 via AOMEI Backupper

Preparations: please first install or connect the target hard drive to your computer. Make sure it is detected. Then, install and run AOMEI Backupper Professional.

Note: the target hard drive or the selected partition on target drive will be overwritten. Back up important files in advance if necessary.

Step 1. Select Clone option on the left side of the main interface. Then, select System Clone to transfer OS.

System Clone

Step 2. The program will automatically select source partitions including OS drive and other boot required partitions. Therefore, you just need to select another hard drive as destination location (here is Disk1), and then click Next.

Destination Disk

If the destination location is a partition, a window will pop to prompt that this partition will be deleted or overwritten.

Step 3. On the Operation Summary window, you can preview the operation: source partitions to target hard drive. If there is no problem, click Start Clone to perform the operation. When it’s completed, click Finish.

Preview Settings

Please tick SSD Alignment if you want to migrate operating system to SSD. It can improve SSD’s performance and prolong its lifespan.
The Sector By Sector Clone mode will copy all the sectors no matter used or not. If you want to transfer OS to new hard drive with only used sectors copied, just keep the default intelligent mode.

Step 4. Shut down your computer. Replace the cloned drive with the original drive, start your computer, press the related key to enter BIOS and then change boot order for the new hard drive, then press F10 to save the changes. Then, the Windows will boot from cloned drive.


  • Besides the disk or system cloning feature, you still can transfer OS to another hard drive by creating a system image first and then restoring system image to another hard drive. If your computer is unbootable, you still can restore the system image under bootable media.

  • If you want to know how to transfer operating system from one computer to another with dissimilar hardware, please refer to clone old PC to a new one.


That’s all for moving OS to another drive. AOMEI Backupper Professional is a powerful OS cloning tool which makes OS or disk transferring easier for common users. With it, you can successfully boot your computer from the cloned hard drive. Also, it still works for moving system reserved partition to another drive.

For advanced users, the software also provides command line clone, i.e. clone hard drive from command prompt, to complete unattended task. For administrators of companies, the Server edition is capable of OS migration to new drive on Windows Server operating systems. Go for it and enjoy your new journey.