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Unallocated space on my system disk

I've noticed how I have a small part of unallocated space on the disk after doing a system image restore.

I'm not really sure where this unallocated space comes and why it's there. I have tried to expand the main system partition to make use of this unallocated space but I don't get that option in Windows Disk Management.

Checking the source data in AOMEI Backupper, I see the same unallocated space. However, when choosing to make a new system backup, it's not included. That's why I'm wondering where it comes from and why it's later included in the backup and also restored onto the actual disk during restore?

This is what it looks like in Windows Disk Management

This is what it looks like when doing a new system backup. As you can see, the unallocated space isn't on this list of what will be backed up

Yet, this is what the source data looks like after the backup. Where you again can see this extra, unallocated space of the disk image. Even when it wasn't on the list of what would be backed up

How can I make sure this unallocated space isn't included in the system image and later ends up on my physical disk when performing a restore of the system image?


  • @WebMaximus, System backup will back up system-related partitions only. The unallocated space is not a partition, so it will not be backed up. Generally, all space on the disk is unallocated before creating partitions.
    The backup doesn't include unallocated space. When you restore, it will restore partitions to the destination location you selected.
  • edited November 2021
    So what you're saying is that if I start by making sure the disk is absolutely clean, only consisting of a huge block of unallocated space, restoring a system image I made earlier will result in not having this unallocated space?

    Sorry about the late follow-up BTW, for whatever reason, never received a notification I had an answer to my question.
  • Just gave it another shot and the result doesn't reflect what you're saying will happen.

    I started booting from AOMEI Bootable Media and then chose the command line utility to run Diskpart. To start by completely wiping everything on the destination disk. Below is what it looked like. Where you can see how the disk is completely blank

    Also in AOMEI during the restore, the destination disk is seen as completely blank with nothing on it

    Also on the AOMEI Operation Summary page, the same is true with a completely blank disk with 0.00 KB used

    Yet after the restore operation is completed, the same 24 MB unallocated block is back as seen here

    How can this be when you say nothing but system partitions are backed up and later restored?
  • @WebMaximus, You can delete the 497MB partition and then add the unalocated space to C: drive.
  • Awesome, thanks!

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