By Ivy / Last Updated December 30, 2020

A Scenario: You Want to Extend C Drive in Windows 7 Without Formatting

“I have a Dell laptop and the c drive is virtually full, such that some of the larger updates cannot be downloaded. With some of the smaller update files I have managed it by emptying the recycle bin. It’s a troublesome business. Any suggestion?”

C Drive Is Out of Space

Maybe, you were confronted with this problem. How did you solve it? Deleting some old files or unusable files? Yes, your problem was solved temporarily. But you will encounter the problem again and again later. Then how do you do? Do as before? It’s not a wise choice. Below, we will show you a greater way.

The C Drive Is Running Out in Windows 7

After computers occupy an increasingly important position in our work and life, extending a certain partition (C drive) in Windows 7/8/10, etc without formatting is becoming an increasingly concerning question. The more you use your computer, the more files you save on your computer. Thus, someday, you will receive a low disk space warning from your computer.

Ways to Fix Low Disk Space Warning in Windows 7

1. Delete some old files or unusable files etc. Some users try this way. Of course, you can. However, if you do not try to find a greater way, you can only delete again and again.

2. Replace the old drive with a large one. Some users try this. It may be better that the first way. But it still not good enough. You need to prepare a large hard drive and backup your data on the old drive and restore it.

3. Add space to C drive in Windows 7. This way will be much better than the above two. In this way, you don’t need to execute operations again and again. At the same time, you still don’t need to prepare another disk.

In short, adding space to C drive in Windows 7 is the best way to fix low disk space warning. The detailed step you can see from below.

How to Increase System Partition in Windows 7 from D Drive

There are three ways you can extend C partition in Windows 7, including extend C drive via Disk Management, extend C drive by Diskpart, extend C drive with AOMEI Backupper. They all have their features.

Increase C Drive via Disk Management

Disk Management comes with Windows 7/8/10/XP etc which is considered a useful tool to help users fix partition and disk problems. To extend partition, you can do as follow.

Step 1: Click Start, then right-click Computer and select Manage

Step 2: Click Disk Management in the Computer Management window, then you will see all the disks and corresponding volumes

Step 3: Click C volume and select Extend Partition

Step 4: Specify the space you want to add to C volume, click Next and Finish.

However, there are still some situations Disk Management does not work. See below:

1. If you try to extend system partition which is not NTFS or RAW formats, you will find it greyed out.

2. If you try to extend a primary partition, and there is no adjacent unallocated space right beside the partition you want to increase, you will find it greyed out as well.

3. If you try to extend a logical partition, and there is only unallocated space and no free space right after the partition you want to increase, you will find Extend partition Grayed out.

Extend Volume Grayed Out

Add Space to C Drive in Windows 7 via Diskpart

The same as Disk Management, Diskpart is a Windows built-in tool. We use this free tool to manage partition and disk by running a command line through scripts or direct inputting commands. When Disk Management does not work, it will be a way. To extend partition, you can do as follows:

Step 1: Tap on “Win + R” to open Run window, type diskpart.exe and press enter


Step 2: Type “list disk” and press enter

Step 3: Type “select disk n”, press enter. n refers to the number of the disk

Step 4: type “select volume n”, press enter. n refers to the number of the C volume.

Step 5: type “extend size=n”, press enter. n refers to the space you want to add to C drive.

Step 6: type exit and leave this window.

Extend C Drive via Diskpart

However, it still has a drawback. When there is no allocated space on your disk, you cannot extend it. So it’s still not perfect. Thus, you have to create an unallocated space or move the existing unallocated space to C drive. If you want to move partition, I recommend you a third-party tool AOMEI Partition Assistant. With it, you can easily move partition. Aside by that, it still has many useful functions like Merge Partition, Extend Partition, Convert MBR to GPT or Convert GPT to MBR, Resize Partition, Wipe Partition etc. Then, let’s continue to see the third way.

Increase C Drive in Windows 7 without Formatting through AOMEI Partition Assistant

AOMEI Partition Assistant Professional is a software designed for Windows Windows 7/8/10 etc, which can meet their needs from common users to high-tech talents. If you are using Windows Server 2019, 2016, 2012 (R2), 2008 (R2), you can use AOMEI Partition Assistant Server. Now, coming into our point-extend C drive in Windows 7 without formatting.

For a free trial, you can download the Demo version of AOMEI Partition Assistant Professoinal to preview the process.

Step 1. Launch it and enter the main page, then select "All Tools" and "Extend Partition Wizard".

Extend Partition Wizard

Step 3: Select an Operation Method to extend C drive in Windows7. After the disk information loading finish, click Next

Step 4: Select a partition to shrink some free space or click here to extend partition by unallocated space on the disk.

Step 5: Specify a size for C drive you want to extend and click Next.

Notice: From above window, you can see a Minimum Partition Size and a Maximum Partition Size, you can drag the blockage to specify it size or manually input a size in the box after Partition New Size.

Step 6: Preview the operation and click Proceed if you ensure you want to do it. Then, wait for the result.


The above three methods can extend C drive in Windows 7 successfully without formatting. But once there is no allocated space right beside the target partition, Disk Management and Diskpart will be unavailable unless you download a third-party tool to move it. However, in AOMEI Partition Assistant, you can extend it from shrunken space or unallocated space. At the same time, it can finish all the operations independently without another utility.