Why I Cannot Extend C Drive with Unallocated Space?

Here's the thing: the Extend Volume option is greyed out when I try to extend my C drive. Why can't I extend the C drive with unallocated space? Tried a few 3rd party software, but none of them can help. Really needs some help here. Thanks in advance!

Best Answered by

Oliver· Answered on Dec 15, 2023

There are two most possible reasons why you cannot extend C drive with unallocated space:

  • The unallocated space is not adjacent to the C drive;
  • Disk Management does not support operations to extend FAT, exFAT, and EXT partitions.

To deal with these kinds of issues, you can resort to a powerful partition management tool - EaseUS Partition Master Professional. This software breaks through Windows limitations and allows you to manage partitions easily.

Free Download 

Windows 11/10/8/7100% Secure

You can use EaseUS Partition Master to extend the C drive with unallocated space across partitions. It can also extend FAT or other format partitions. Here's the guide:

Step 1. Open EaseUS Partition Master, select C drive, and choose "Resize/Move."

Step 2. Drag the partition panel to extend the C drive with unallocated space no matter where it is. Then, click "OK" and "Execute * Task(s)" to start the process.

If the unallocated space is on a different disk, you can also extend the C drive from another disk via this tool:

Step 1. Open EaseUS Partition Master, right-click the C drive, and select "Advanced" > "Extend with 2nd Disk."

Step 2. In the next window, hit "Customize Plan" to continue.

Step 3. Then, choose a customize extension plan and click "Next."

Step 4. Configure the extended partition for the C drive to be at the end of a certain partition and click "Proceed."

You can also use Disk Management to resolve some of the problems. It is noteworthy that if the C drive is FAT32, you have to convert FAT32 to NTFS, which will definitely cause data loss on the drive if you use Disk Management. Therefore, it's highly recommended to leave the job to a professional third-party tool.

Free Download 

Windows 11/10/8/7100% Secure

People Also Ask

Can You Move C Drive to New Disk?

If your C drive is out of space and you want to replace the disk with a larger one, can you move C drive to new disk? Continue reading on this page, and you'll get the answer.


Dec 28, 2023

I Need Solid Ways That Can Create a New Partition on the Hard Drive, Help

If you are looking for solid ways to create a new partition on the hard drive, read this article, in which you can find the partition methods with detailed tutorials.


Aug 09, 2023

Unable to Create Partitions Because the Disk Already Contains the Maximum Numbers of Partitions

Have you ever encountered the error message: the disk already contains the maximum number of partitions? If you are having a hard time with this problem, you should read this article that contains a solid way to fix it.


Aug 09, 2023

What Is the Safest Way to Merge Partitions?

Many ways can help users merge partitions. However, which one is the safest way to merge partitions? You will find the answer and the detailed guide in this article.


Aug 31, 2023

Is It Possible to Fix EFI Partition Too Small to Push Windows Updates

If your EFI Partition is too small to push Windows updates, you are coming to the right place. In this article, you will find a reliable solution and detailed steps.


Aug 09, 2023

Missing Unallocated Space After the Volume Shrink, How to Resolve?

Are you finding a practical solution for missing unallocated space after the volume shrink issue? This page can provide reliable methods to help you fix this problem.


Sep 13, 2023