Extend system partition

Extend system partition on Windows Server 2016

Unlike normal data drives, system partition is the drive that Operating System installed in or booting from, so you’d better pay more attention when extending system partition, otherwise, it may cause system boot failure.

This article shows how to extend system partition on Windows Server 2016 without losing data. Shrink data partition to extend system drive by simply dragging and dropping on the disk map.

Extend system partition

Extend system partition with Disk Management

Some people like to use Windows native utility, Disk Management snap-in has Extend Volume to increase partition size, but to extend system drive on Windows Server 2016, this utility is not the best choice. Why?

Before extending a partition, you must get Unallocated space. To get this space, you have two options in Disk Management: delete or shrink another partition. After deleting a partition, all disk space will be converted to Unallocated. After shrinking a partition with Shrink Volume functionality, part of the unused space will be converted to Unallocated and you won’t lose files in it.

In most of the servers, programs and part of Windows services are running from the adjacent partition (D:), so you cannot delete it to extend system partition C.

If you want to extend system C: drive by shrinking D, it is impossible, because Extend Volume only works when there is adjacent Unallocated space on the right side. After shrinking the adjacent drive D, Unallocated space is produced on the right side of D rather than C, so Extend Volume is disabled for partition C.

Extend Volume greyed out

The only way to extend system partition C on Server 2016 is running 3rd-party disk partition manager software, which can shrink D and produce Unallocated space on the left directly, or move Unallocated to the left side if you have shrank D.

Extend system drive with partition software

The operations that Disk Management can do are safe in most situations, but it is not the case to third party software.

When shrinking and extending disk partitions, all related parameters must be modified correctly. In addition, all files in the partition that you are shrinking should be moved to new locations. Different with extending data drives, when extending system partition boot record should be updated, too. If any software error or hardware issue occur during this process, an unreliable partition software could cause system boot failure, partition corruption or data loss. So the first and most important step is backing up and running safe partition tool.

Among these server partition software, NIUBI Partition Editor is recommended as the best choice, because:

  • It is integrated with innovative 1 Second Rollback technology to ensure system and data intact. It creates snapshot of disk partitions and automatically reverts the server to original status if anything goes wrong. If it happens, server could back online without damage in a short time.
  • Hot-Resize technology helps extend system partition on the fly. (Close the running programs and opening files/folders in partition D before starting NIUBI.)
  • Unique file-moving algorithm helps shrink D and extend system drive C 30% to 300% faster.
  • Virtual mode to avoid mistake, the operations you do will be listed as pending for preview. You can cancel any unwanted operations before clicking Apply to confirm.
  • Cancel-at-will technology allows you cancelling the ongoing operations without losing data, so you won’t lose control during the whole process.

How to shrink D to extend system partition C

Download NIUBI Partition Editor, you’ll see all separate partitions on top right, all hard disks with graphical partition configuration on bottom right. All available operations to selected disk or partition are listed on the left side. To most of the servers, there is another drive (D:) in the same disk, you just need to drag and drop on the disk map to shrink it and extend OS partition.

Resize Volume

Steps to extend system partition on Windows Server 2016:

Step 1 Right click the adjacent drive D and select “Resize/Move Volume”. Drag the left border rightwards to shrink it.

Shrink D

Click OK, 20GB Unallocated space is produced on the left side of D and there is a pending operation added on bottom left.

Drive D shrank

Step 2 Right click drive C and select “Resize/Move Volume” again. Drag the right border rightwards to combine the Unallocated space.

Extend C drive

Click OK, the system partition C is extended to 50GB.

Extend partition C

As I said above, this partition software is working in virtual mode, to modify real disk partition, remember to Click Apply on top left to confirm.

Video guide

If you have shrank D or there is not enough free space in D, you need an additional step to move Unallocated space to behind C drive. Watch the video how to shrink data drives to extend system volume on Server 2016.

In Summary

Windows Disk Management cannot extend system partition in Server 2016 by shrinking any data volumes. You can achieve by deleting the adjacent partition D, but it is not a good idea. The best way to extend system partition on Windows Server 2016 is running reliable partitioning software. Because of the powerful data protection ability, fast file-moving algorithm and other benefits, NIUBI Partition Editor helps you accomplish this task well.