Cannot Extend C Drive on Windows Server 2016 Fixes


This page is about how to extend C drive on Windows server 2016 when it is unable to extend volume on server 2016, I will introduce some very useful solutions to extend C drive without data loss.

Andrew WrightUpdated on Feb 2, 2023

by Andrew Wright

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If you’re using the Windows Server 2016 OS, you may encounter the problem the disk space every now and then – especially the system partition. System partition is always responsible for accommodating all the data of system programs and application. Therefore, it is most likely for the c drive to gets full after a certain period.

Why Cannot Extend Volume Windows Server 2016 - 5 possible causes

extend volume disabled

There are several reasons why you may be unable to extend the C drive on a Windows Server 2016 system:

Cause#1: Insufficient unallocated space: In order to extend the C drive, you need to have unallocated space on the same physical hard drive. If there is no unallocated space, you will not be able to extend the C drive.

The position of the unallocated space matters: The unallocated space shall be at the right side of the c drive. No unallocated space at the right side of c drive? Delete the c drive closeby volume in Disk Management.

If you do not want to delete a volume, you may use 3rd party program Partition Resizer to shrink a volume without losing data, move partitions without losing data.

Cause#2: Disk Management limitations: Windows Server 2016 Disk Management tool has limitations in extending a partition and may not be able to extend the C drive in certain situations.

If the disk is set as MBR, which can hold at most 2TB disk space, it won't allow you to extend extra space to this disk.

Cause#3: File System: If the C drive is formatted with the FAT32 file system, it cannot be extended as this file system does not support partition resizing.

Note: Partition Resizer can safely add space to c drive which has fat32 file system without losing data.

Cause#4: Disk type: If the C drive is a dynamic disk, it cannot be extended using the Disk Management tool.

Partition Resizer can help extend disk space to a dynamic disk.

Cause#5: Disk errors: If there are disk errors or bad sectors, the Disk Management tool may not be able to extend the C drive.

In such cases, you can use third-party partitioning software to extend the C drive or backup your data and perform a fresh installation of the operating system.

For most cases, extend volume is disabled due to no adjacent unallocated space to c drive.

Extend the C Partition Without Losing data with Partition Resizer

If there is no unallocated space available on your hard disk, then you may need to delete the backend partition to extend the c-drive. This isn’t a simple task and require a higher knowledge of disk management utility and its uses. It also includes a huge risk of data loss.

For this situation, there are several third-party partition resizer software available on the market. And IM-magic Server Edition is one of the best disk management software. It allows you to extend, shrink, and manage your partitions without any kind of data loss.

The IM-Magic Partition Resizer Server allows you to adjust the unallocated space even if it is not available to right side of the c-drive. You can follow the steps to extend c partition when there is no unallocated space.

[Guide] Steps to extend volume without data loss

This step by step guide will show you the right way to extend any volume using  IM-Magic Partition Resizer Unlimited edition.

Step-1  Download install, and launch the program.

Step-2 Right click the large volume to produce unallocated free space.

Steps to resize your disk partition
Steps to resize your disk partition

Extend the partition without data lossShrink the partition without data loss

Step-3  Then right click c and drag the border to acquire the free space.

Steps to resize your disk partition
Steps to resize your disk partition

Step-4 Apply the changes.

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