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Partition Assistant: Unable to extend C partition

I split my original C drive (SSD) of my laptop to a C drive (100GB) and D drive (400GB). I want to shrink the D drive by 20GB and add the regained storage to C drive. I am able to reduce the D drive space but unable to add the recovered space to C drive. It doesnt give me the option to extend the C drive. Can you guide me how to do that?


  • edited November 16
    Hello Muralin, I hear you have used PA, and now you want to shrink partition D by 20GB and then expand partition C by 20GB. You may use PA to Move Partition D to make room for Partition C to expand.
    I have used PA Pro for years, it has many good features, however in my opinion, 1 of the 2 features I do not recommend most people use is shrinking a partition. Disk Management can shrink almost all partitions very quickly and without error, while PA could take very long, or even result in errors. If you are advanced, you could even use Diskpart to shrink partition, but Disk Management is best.
    PA is the best Windows tool I know of to Move Partition.
    If PA needs to reboot, and prompts you to choose between PA-app-WinPE mode, and PA-app-PreOS mode, it is recommended to always choose PA-app-WinPE mode. If you are advanced, you could use PA-USB-WinPE mode.
    Partition Assistant WinPE USB:
    Add custom drivers, such as NVMe, if necessary.
    Aomei WinPE Builder USB:
    Partition Assistant, Backupper, Recuva, 7zip, OSF Mount, CPU-Z, Bootice, diskmgmt.msc. Does not support any additional drivers, such as some internal NVMe disks.

  • @AiArtisan: Thanks for your guidance. I used Disk Management to shrink D by 20GB. Now I have 20GB of unallocated storage but I am unable to add this to extend C:. Any thoughts on how I could do that?
  • If there is no free space immediately after partition C, you could use PA to Move Partition D.
    Please post a screenshot from PA.

  • @aiArtisan: Here are 2 screenshots (1) showing all the partitions. Notice the 17GB unallocated space next to D (2) shows the screen when I try to "move and resize" C.
  • edited November 17
    If there is no free space immediately after partition C, you could use PA to Move Partition D.
    Before making major disk changes with any program, always make a backup of your essential files to a USB stick, then remove the stick.
  • @Muralin, We suggest that you can first close Bitlocker of C: drive.
    Then, you can use Partition Assistant to move the D drive so that the unallocated space is next to C drive, and apply and process the operation.
    After that, you can extend C: drive via AOMEI Partition Assistant or Windows Disk Management.
  • thanks. Turning off Bitlocker made the trick.
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